Scholars@Duke
Emily M. Klein

Emily M. Klein

University Distinguished Service Professor Emeritus in the Division of Earth and Climate Sciences
Earth and Climate Sciences
ek4@duke.edu
Box 90328, Durham, NC 27708-0328
Room A115, LSRC-A Wing, Box 90328, Durham, NC 27708

Scholarly Works - Journal articles

Magmatism at Incipient Rift, Galapagos Triple Junction: Tapping the Off-Axis East Pacific Rise Melting Regime

Journal article Geophysical Research Letters · October 28, 2025 Incipient Rift (IR) is the latest in a sequence of short-lived rifts that form ridge-ridge-ridge triple junctions with the East Pacific Rise (EPR) in the Galapagos triple junction region. IR extends ∼65 km southeastward from its intersection with the EPR a ... Full text Cite

Evidence of South American lithosphere mantle beneath the Chile mid-ocean ridge

Journal article Earth and Planetary Science Letters · October 15, 2023 Numerous geochemical studies on mid-ocean ridge basalts have established the presence of both compositional and lithological heterogeneities in the upper mantle. These studies have successfully constrained the composition and age of the chemical heterogene ... Full text Cite

Measuring H2O concentrations in olivine by secondary ion mass spectrometry: Challenges and paths forward

Journal article American Mineralogist · May 1, 2023 Trace concentrations of H2O in olivine strongly affect diverse mantle and magmatic processes. H2O in olivine has been difficult to accurately quantify due to challenges in sample preparation and measurement, as well as significant uncertainties in standard ... Full text Cite

Gravity Anomalies and Implications for Shallow Mantle Processes of the Western Cocos-Nazca Spreading Center

Journal article Geophysical Research Letters · March 16, 2023 This study analyzes up-to-date gravity data in the Galapagos triple junction region to understand crustal structure and melt distribution beneath the propagating Cocos-Nazca spreading center (CNSC). Application of a standard thermal model to the mantle Bou ... Full text Cite

Upper Crustal Structure of Superfast-Spread Oceanic Crust Exposed at the Pito Deep Rift: Implications for Seafloor Spreading

Journal article Geochemistry Geophysics Geosystems · March 1, 2023 A tectonic window into the upper 2,000 m of oceanic crust generated at the superfast spreading (∼142 mm/yr) southern East Pacific Rise exposes a continuous layered structure of basaltic lavas and sheeted dikes over gabbroic rocks. This relatively simple st ... Full text Cite

The Global Biogeochemical Cycle of Arsenic

Journal article Global Biogeochemical Cycles · November 1, 2022 Direct exploitation and use of arsenic resources has diminished in recent years, but inadvertent mobilizations of As from mineral extractions (metal ores, coal, and phosphate rock) are now as much as ten-fold greater (1,500–5,600 × 109 g/yr) tha ... Full text Open Access Cite

Global Biogeochemical Cycle of Lithium

Journal article Global Biogeochemical Cycles · August 2021 AbstractThe total human mobilization of Li from the Earth's crust, >1,000 × 109 g/year, is much larger than Li mobilized by the natural processes of chemical and mechanical weathering (94 and 132 × 1 ... Full text Open Access Cite

Global Biogeochemical Cycle of Fluorine

Journal article Global Biogeochemical Cycles · December 1, 2020 This review provides a synthesis of what is currently known about the natural and anthropogenic fluxes of fluorine on Earth, offering context for an evaluation of the growing environmental impact of human-induced F mobilization and use. The largest flux of ... Full text Cite

The Evolution of Seafloor Spreading Behind the Tip of the Westward Propagating Cocos-Nazca Spreading Center

Journal article Geochemistry Geophysics Geosystems · June 1, 2020 At the Galapagos triple junction in the equatorial Pacific Ocean, the Cocos-Nazca spreading center does not meet the East Pacific Rise (EPR) but, instead, rifts into 0.4 Myr-old lithosphere on the EPR flank. Westward propagation of Cocos-Nazca spreading fo ... Full text Cite

Reply to Selin: Human impacts on the atmospheric burden of trace metals.

Journal article Proceedings of the National Academy of Sciences of the United States of America · March 2018 Full text Cite

Global biogeochemical cycle of vanadium.

Journal article Proceedings of the National Academy of Sciences of the United States of America · December 2017 Synthesizing published data, we provide a quantitative summary of the global biogeochemical cycle of vanadium (V), including both human-derived and natural fluxes. Through mining of V ores (130 × 109 g V/y) and extraction and combustion of fossi ... Full text Open Access Cite

Tectonic and magmatic segmentation of the Global Ocean Ridge System: A synthesis of observations

Journal article · January 1, 2016 Mid-ocean ridges display tectonic segmentation defined by discontinuities of the axial zone, and geophysical and geochemical observations suggest segmentation of the underlying magmatic plumbing system. Here, observations of tectonic and magmatic segmentat ... Full text Open Access Cite

Global rate and distribution of H2 gas produced by serpentinization within oceanic lithosphere

Journal article Geophysical Research Letters · January 1, 2016 It has recently been estimated that serpentinization within continental lithosphere produces H2 at rates comparable to oceanic lithosphere (both are ~1011 mol H2/yr). Here we present a simple model that suggests that H ... Full text Cite

Emily M. Klein

Journal article OCEANOGRAPHY · December 1, 2014 Link to item Cite

Reconciling geochemical and geophysical observations of magma supply and melt distribution at the 9N overlapping spreading center, East Pacific Rise

Journal article Geochemistry Geophysics Geosystems · November 1, 2012 Early studies of mid-ocean ridge discontinuities, such as transform faults and overlapping spreading centers, suggested a lower magma supply compared to ridge segment centers. This is reflected in bathymetrically deeper ridge axes, decreased hydrothermal a ... Full text Open Access Cite

Volatile abundances and oxygen isotopes in basaltic to dacitic lavas on mid-ocean ridges: The role of assimilation at spreading centers

Journal article Chemical Geology · August 7, 2011 Most geochemical variability in MOR basalts is consistent with low- to moderate-pressure fractional crystallization of various mantle-derived parental melts. However, our geochemical data from MOR high-silica glasses, including new volatile and oxygen isot ... Full text Open Access Cite

Dacite petrogenesis on mid-ocean ridges: Evidence for oceanic crustal melting and assimilation

Journal article Journal of Petrology · December 1, 2010 Whereas the majority of eruptions at oceanic spreading centers produce lavas with relatively homogeneous mid-ocean ridge basalt (MORB) compositions, the formation of tholeiitic andesites and dacites at mid-ocean ridges (MORs) is a petrological enigma. Erup ... Full text Cite

The Effectiveness of Arsenic Remediation from Groundwater in a Private Home

Journal article GROUND WATER MONITORING AND REMEDIATION · 2010 Full text Link to item Cite

Significance of widespread low effusion rate eruptions over the past two million years for delivery of magma to the overlapping spreading centers at 9°N East Pacific Rise

Journal article Earth and Planetary Science Letters · April 15, 2009 Ever since the discovery that the mid-ocean ridge axis deepens at most axial discontinuities, there has been vigorous debate about whether ridge axis depth and shape reflect magma supply. Here we report evidence, from one of the most thoroughly studied rid ... Full text Cite

Compositions of dikes and lavas from the Pito Deep Rift: Implications for crustal accretion at superfast spreading centers

Journal article Journal of Geophysical Research Solid Earth · March 4, 2009 The northwest trending walls of the Pito Deep Rift (PDR), a tectonic window in the southeast Pacific, expose in situ oceanic crust generated ∼3 Ma at the superfast spreading southern East Pacific Rise (SEPR). Whole rock analyses were performed on over 200 ... Full text Cite

Cracking of lithosphere north of the Galapagos triple junction

Journal article Geology · May 1, 2008 The Galapagos triple junction is a ridge-ridge-ridge triple junction where the Cocos, Nazca, and Pacific plates meet around the Galapagos microplate. Directly north of the large scarps of the Cocos-Nazca Rift, a 250-km-long and 50-km-wide band of northwest ... Full text Cite

Role of upwelling hydrothermal fluids in the development of alteration patterns at fast spreading ridges: Evidence from the sheeted dike complex at Pito Deep

Journal article Geochemistry Geophysics Geosystems · May 1, 2008 Alteration of sheeted dikes exposed along submarine escarpments at the Pito Deep Rift (NE edge of the Easter microplate) provides constraints on the crustal component of axial hydrothermal systems at fast spreading mid-ocean ridges. Samples from vertical t ... Full text Cite

Petrology and geochemistry of primitive lower oceanic crust from Pito Deep: Implications for the accretion of the lower crust at the Southern East Pacific Rise

Journal article Contributions to Mineralogy and Petrology · November 1, 2007 A suite of samples collected from the uppermost part of the plutonic section of the oceanic crust formed at the southern East Pacific Rise and exposed at the Pito Deep has been examined. These rocks were sampled in situ by ROV and lie beneath a complete up ... Full text Cite

Temporal and spatial variability in the composition of lavas exposed along the Western Blanco transform fault

Journal article Geochemistry Geophysics Geosystems · November 1, 2005 The northern scarp of the Western Blanco Transform (BT) Fault Zone provides a "tectonic window" into crust generated at an intermediate-rate spreading center, exposing a ∼2000 m vertical section of lavas and dikes. The lava unit was sampled by submersible ... Full text Cite

Four-dimensional upper crustal construction at fast-spreading mid-ocean ridges: A perspective from an upper crustal cross-section at the Hess Deep Rift

Journal article Journal of Volcanology and Geothermal Research · June 15, 2005 The faulted walls of the Hess Deep Rift in the equatorial Pacific provide one of the few significant tectonic windows into the oceanic crust created at a fast-spreading mid-ocean ridge. The 5000-m-deep rift graben exposes a slightly dismembered section of ... Full text Cite

Counter-rotating microplates at the Galapagos triple junction.

Journal article Nature · February 2005 An 'incipient' spreading centre east of (and orthogonal to) the East Pacific Rise at 2 degrees 40' N has been identified as forming a portion of the northern boundary of the Galapagos microplate. This spreading centre was described as a slowly diverging, w ... Full text Cite

Earth science: spread thin in the Arctic.

Journal article Nature · June 2003 Full text Cite

Geochemical relationships between dikes and lavas at the Hess Deep Rift: Implications for magma eruptibility

Journal article Journal of Geophysical Research Solid Earth · April 10, 2003 Differences in composition and phenocryst assemblages between dikes and lavas collected from 1-m.y.-old oceanic crust exposed at the Hess Deep Rift have important implications for density filtering of magmas ascending through the upper crust in mid-ocean r ... Cite

Geochemical relationships between dikes and lavas at the Hess Deep Rift: Implications for magma eruptibility

Journal article Journal of Geophysical Research: Solid Earth · April 2003 Differences in composition and phenocryst assemblages between dikes and lavas collected from 1‐m.y.‐old oceanic crust exposed at the Hess Deep Rift have important implications for density filtering of magmas ascending through the upper crust in mid ... Full text Cite

Geochemistry of dikes and lavas from the north wall of the Hess Deep Rift: Insights into the four-dimensional character of crustal construction at fast spreading mid-ocean ridges

Journal article Journal of Geophysical Research Solid Earth · October 10, 2002 An investigation of ∼1-m.y.-old dikes and lavas from the north wall of the Hess Deep Rift (2°15′N, 101°30′W) collected during Alvin expeditions provides a detailed view of the evolution of fast spreading oceanic crust. The study area encompasses 25 km of a ... Cite

Geochemistry of dikes and lavas from the north wall of the Hess Deep Rift: Insights into the four‐dimensional character of crustal construction at fast spreading mid‐ocean ridges

Journal article Journal of Geophysical Research: Solid Earth · October 2002 An investigation of ∼1‐m.y.‐old dikes and lavas from the north wall of the Hess Deep Rift (2°15′N, 101°30′W) collected during Alvin expeditions provides a detailed view of the evolution of fast spreading oceanic crust. Th ... Full text Cite

Structure of uppermost fast‐spread oceanic crust exposed at the Hess Deep Rift: Implications for subaxial processes at the East Pacific Rise

Journal article Geochemistry, Geophysics, Geosystems · January 2002 The uppermost 2 km of the oceanic crust created at the fast spreading (135 mm yr−1, full rate) equatorial East Pacific Rise (EPR) is exposed for tens of kilometers along escarpments bounding the Hess Deep Rift. Mosaics of large ... Full text Cite

Basalt compositions from the Mid-Atlantic ridge at the smark area (22°30'N to 22°50'N) - Implications for parental liquid variability at isotopically homogeneous spreading centers

Journal article Earth and Planetary Science Letters · May 22, 2001 Major- and trace-element analyses of over 50 well-located samples from the third segment south of the Kane Transform Fault are reported. These can be grouped into four age groups based on structural relations and paleomagnetic data. Although no spatial rel ... Full text Cite

Petrology and Sr, Nd, and Pb isotope geochemistry of mid-ocean ridge basalt glasses from the 11°45′N to 15°00′N segment of the East Pacific Rise

Journal article Geochemistry Geophysics Geosystems · November 1, 2000 Basaltic glasses from the geophysically well-studied section of the East Pacific Rise (EPR) between 11°45′N to 15deg;00′N range from normal mid-ocean ridge basalts (MORB) to transitional MORB and their major element variations correlate with isotopic and t ... Full text Cite

Uranium-series age constraints on lavas from the axial valley of the Mid-Atlantic Ridge, MARK area

Journal article Earth and Planetary Science Letters · October 17, 2000 Mass spectrometric measurements of 230Th-226Ra, 235U-231Pa and 238U-230Th disequilibria are used to determine eruption ages for four mid-ocean ridge basalts from the median valley of the Mid ... Full text Cite

Evidence for subduction-related contamination of the mantle beneath the southern Chile Ridge: Implications for ambiguous ophiolite compositions

Journal article Special Paper of the Geological Society of America · January 1, 2000 The recent discovery of convergent-margin geochemical signatures along the southern Chile Ridge spreading center may have implications for the interpretation of ophiolite provenance. The location of the ridge near a ridge-trench-trench (RTT) triple junctio ... Full text Cite

Age constraints on crustal recycling to the mantle beneath the southern Chile Ridge: He-Pb-Sr-Nd isotope systematics

Journal article Journal of Geophysical Research Solid Earth · March 10, 1999 Basalts from the four southernmost segments of the subducting Chile Ridge (numbered 1-4 stepping away from the trench) display large variations in Sr, Nd, Pb, and He isotope and trace element compositions. Klein and Karsten [1995] showed that segments 1 an ... Full text Cite

The biogeochemistry of phosphorus after the first century of soil development on Rakata Island, Krakatau, Indonesia

Journal article Biogeochemistry · January 1, 1998 This study examined the accumulation of organic carbon (C) and fractions of soil phosphorus (P) in soils developing in volcanic ash deposited in the 1883 eruption of Krakatau. Organic C has accumulated at rates of 45 to 127 g/m2/yr during 110 ye ... Full text Cite

Petrogenesis of axial lavas from the southern Chile Ridge: Major element constraints

Journal article Journal of Geophysical Research Solid Earth · January 1, 1997 We present major element glass data for 163 rock samples collected from four ridge segments of the southern Chile Ridge between the Chiloe Fracture Zone and the Chile Margin Triple Junction, including the segment currently being subducted at the Chile Tren ... Cite

Subduction zone geochemical characteristics in ocean ridge basalts from the southern Chile Ridge: Implications of modern ridge subduction systems for the Archean

Journal article Lithos · January 1, 1996 The southern portion of the Chile Ridge is one of few sites where active subduction of a spreading center and its consequences for ridge axis magmatism can be investigated. New major element, trace element, and isotopic data for lavas recovered from the ri ... Full text Cite

New insights in crustal accretion expected from Indian Ocean spreading centers

Journal article Eos · January 1, 1995 Since a large percentage of the mid-ocean ridge system remains uncharted and unsampled, studying the diverse processes involved in the generation of new oceanic crust is an ambitious goal that requires international cooperation. The Ridge InterDisciplinary ... Cite

Ocean-ridge basalts with convergent-margin geochemical affinities from the Chile Ridge

Journal article Nature · January 1, 1995 COLLISIONS between active spreading centres and subduction zones have occurred frequently throughout Earth history1. Of the few sites of ridge subduction active today, the southern Chile Ridge has the simplest tectonic history2. We re ... Full text Cite

New insights in crustal accretion expected from Indian Ocean Spreading Centers

Journal article Eos Transactions American Geophysical Union · January 1, 1995 Since a large percentage of the mid‐ocean ridge system remains uncharted and unsampled, studying the diverse processes involved in the generation of new oceanic crust is an ambitious goal that requires international cooperation. The Ridge InterDisciplinary ... Full text Cite

The origin of bathymetric highs at ridge-transform intersections: A multi-disciplinary case study at the Clipperton Fracture Zone

Journal article Marine Geophysical Researches · February 1, 1994 Bathmetric highs on the old crust proximal to ridge-transform intersections (RTIs), termed "intersection highs", are common but poorly understood features at offsets of fast to intermediate rate spreading centers. We have combined new reflection seismic, p ... Full text Cite

Fresh basalts from the Pacific-Antarctic Ridge extend the Pacific geochemical province

Journal article Nature · January 1, 1993 OVER the past several decades, the examination of volcanic rocks recovered from mid-ocean ridges and ocean islands worldwide has led to the identification of large-scale geochemical provinces reflecting compositionally distinct domains in the Earth's mantl ... Full text Cite

Geochemistry of basalts from the Southeast Indian Ridge, 115°E- 138°E

Journal article Journal of Geophysical Research · January 1, 1991 The ocean basin south of Australia contains the Australian-Antarctic Discordance, an anomalously deep portion of the Southeast Indian Ridge that marks a boundary between isotopic provinces characteristic of the Indian and Pacific oceans. Samples recovered ... Full text Cite

Ocean Ridge Magmatic and Hydrothermal Geochemical Processes

Journal article Reviews of Geophysics · January 1991 Full text Cite

Ocean-ridge basalt compositions correlated with palaeobathymetry

Journal article Nature · January 1, 1990 KLEIN and Langmuir1 investigated the relationships between the chemistry and water depth of eruption of zero-age mid-ocean-ridge basalts around the world. They showed that the regionally averaged values of the major-element oxides Na2 ... Full text Open Access Cite

Local versus global variations in ocean ridge basalt composition: A reply

Journal article Journal of Geophysical Research: Solid Earth · 1989 Full text Open Access Cite

Mixing of basalt magmas

Journal article Nature · 1989 Full text Open Access Cite

Isotope evidence of a mantle convection boundary at the Australian-Antarctic Discordance

Journal article Nature · 1988 Basalts from the Southeast Indian Ridge south of Australia form two geographically and isotopically distinct groups that show affinities with either Indian Ocean or Pacific/Atlantic Ocean isotope compositions. The data raise the possibility that there is a ... Full text Open Access Cite

Global correlations of ocean ridge basalt chemistry with axial depth and crustal thickness.

Journal article · December 1, 1987 Thermal modeling independently predicts the observed relationships among basalt chemistry, ridge depth, and crustal thickness resulting from temperature variations in the mantle. Beneath the shallowest and deepest ridge axes, temperature differences of app ... Open Access Cite

Global correlations of ocean ridge basalt chemistry with axial depth and crustal thickness.

Journal article Journal of Geophysical Research · 1987 Thermal modeling independently predicts the observed relationships among basalt chemistry, ridge depth, and crustal thickness resulting from temperature variations in the mantle. Beneath the shallowest and deepest ridge axes, temperature differences of app ... Full text Open Access Cite