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Dewey, JF, Cande S, Pitman WC.  1989.  Tectonic Evolution of the India Eurasia Collision Zone. Eclogae Geologicae Helvetiae. 82:717-734. AbstractWebsite
Cande, SC, Labrecque JL, Haxby WF.  1988.  Plate Kinematics of the South-Atlantic - Chron C34 to Present. Journal of Geophysical Research-Solid Earth and Planets. 93:13479-13492.   10.1029/JB093iB11p13479   AbstractWebsite

A high-resolution seafloor spreading history of the South Atlantic since chron C34 is constrained by a combination of Seasat altimeter data and underway marine geophysical data. A set of 45 finite rotation poles defines the relative position of Africa and South America at roughly 2-m.y. intervals. A set of 12 stage poles constrain the relative motion of these two plates at 5- to 10-m.y. intervals. The position of the stage poles continuously migrates, reflecting the continuously changing azimuths of the fracture zones. Major changes in spreading direction are observed in the Late Cretaceous and early Cenozoic as the fracture zones sweep out broad S-shaped curves similar to the pattern seen on the Kane fracture zone in the central Atlantic. Small offset fracture zones were found to be the most accurate recorders of changes in plate motion; large offset fracture zones, such as the Agulhas-Falkland fracture zone, were the least reliable recorders. At 30°S, spreading rates decrease throughout the Late Cretaceous from a high of 75 mm/yr at the end of chron C34 to a low of 30 mm/yr around chron C27. A period of slow spreading between chron C30 and chron C20 corresponds to a zone of fracture zone proliferation, an increase in the amplitude of geoid anomalies over fracture zones, greater relief on topographic profiles, and locally, evidence of intraplate crustal deformation. Spreading rates increase at chron C20 to about 50 mm/yr and then gradually decrease during the late Paleogene and Neogene. A comparison of synthetic fracture zones based on the South Atlantic stage poles to the observed trends of fracture zones in the equatorial Atlantic indicates that the Vema and Marathon fracture zones were generated by South Atlantic spreading, as opposed to central Atlantic spreading, at least as far back as 35 m.y. ago and possibly 50 m.y. ago.

Pindell, JL, Cande SC, Pitman WC, Rowley DB, Dewey JF, Labrecque J, Haxby W.  1988.  A Plate-Kinematic Framework for Models of Caribbean Evolution. Tectonophysics. 155:121-138.   10.1016/0040-1951(88)90262-4   AbstractWebsite

We define the former relative positions and motions of the plates whose motions have controlled the geological evolution of the Caribbean region. Newly determined poles of rotation defining the approximate spreading histories of the central North and the South Atlantic oceans are given. For the late Jurassic-Early Cretaceous anomaly sequence of the central North Atlantic, we have used previously published∗ definitions of fracture-zone traces and magnetic anomaly picks, redetermining the pole positions and angular rotations for various isochrons on an Evans and Sutherland interactive graphics system. For magnetic anomalies younger than the Cretaceous Quiet Period in both oceans, we (1) used Seasat altimeter data to help define fracture-zone traces, and (2) identified and used marine magnetic anomalies to determine the positions of spreading isochrons along the flowlines indicated by the fracture zones. By the finite difference method, the relative paleopositions and the relative motion history between North and South America were computed. This analysis defines the size and shape (and the rate at which the size and shape changed) of the interplate region between North and South America since the Middle Jurassic. Thus, a plate-kinematic framework is provided for the larger plates pertaining to the Caribbean region, in which can be derived more detailed scenarios for Gulf of Mexico and Caribbean evolution.North and South America diverged to approximately their present relative positions from Late Triassic? to Early Campanian (about 84 m.y. ago) time. This is the period during which the Gulf of Mexico and a Proto-Caribbean seaway were formed. Since the Campanian, only minor relative motion has occurred; from Early Campanian through to Middle Eocene times. South America diverged only another 200 km, and since the Middle Eocene, minor N-S convergence has occurred. These very minor post-Early Campanian motions have probably been accommodated by imperfect shear and compression along the Atlantic fracture zones to the east of the Lesser Antilles, and along the northern and southern borders of the Caribbean Plate. Accordingly, it is suggested that from Campanian time to the present, the relative motions between the North and South American plates have had only minor effects on the structural development of the Caribbean region.Primarily using the data of Engebretson et al.∗∗, the convergence history of Pacific plates with North America was calculated for two points near the western Caribbean. By completing finite difference solutions, the convergence history of the Pacific plates with the Caribbean and South American plates can be approximated. The direction and rate of convergence of the Pacific plates with the Americas may have controlled the style of subduction and possible microplate migration along the North American, South American and western Caribbean boundaries that define the eastern Pacific plate margin.

Cande, SC, Leslie RB, Parra JC, Hobart M.  1987.  Interaction between the Chile Ridge and Chile Trench - Geophysical and Geothermal Evidence. Journal of Geophysical Research-Solid Earth and Planets. 92:495-520.   10.1029/JB092iB01p00495   AbstractWebsite

Geophysical and geothermal data are examined from the three southernmost sections of the Chile Ridge, starting at 44°S and continuing south to the triple junction of the Nazca, Antarctic, and South America plates at 47°S. These sections represent three progressively younger stages in a ridge-trench collision event, corresponding to 3 m.y. before the collision, 1 m.y. before the collision, and culminating in an ongoing collision at the triple junction. Magnetic and bathymetric data across the Chile Rise indicate that there is little change in the configuration of the spreading center as the ridge approaches and then collides with the trench. In the collision zone a “normal” looking rift valley can be traced for 40 km before it disappears beneath the toe of the landward trench slope. There is no evidence for the complex pattern of ridge jumps and spreading center rotations that occurred when the Pacific-Farallon spreading center collided with North America. In contrast, the overriding plate is greatly affected by the ridge collision. The landward trench slope steepens and narrows as the collision zone is approached. At the southern end of the collision zone a ridge associated with the Taitao Fracture Zone is colliding with the trench and may be in the process of being obducted onto the landward trench slope. Geothermal measurements were made along three transects of the margin, corresponding to the time 3 m.y. before the collision, during the collision, and 6 m.y. after the collision. The heat flow measurements in the collision zone document a large pulse of heat associated with the subduction of the ridge: Values as high as 345 mW/m2 were recorded on the lower trench slope. A prominent bottom-simulating reflector (BSR) observed over a wide area of the landward trench slope north of the triple junction, and, more locally, south of the triple junction, is used to expand the grid of heat flow observations. Excellent agreement is found between measured heat flow and estimates of heat flow based on the depth to the BSR. The heat flow measurements compare favorably with a theoretical model assuming conductive heat flow. We estimate that the accretionary prism has been substantially removed in the collision zone and conclude that the landward trench slope is undergoing an episode of rapid tectonic erosion. Periodic ridge collisions in the past may account for the apparent truncation of the Andean forearc region.

Cande, SC, Leslie RB.  1986.  Late Cenozoic Tectonics of the Southern Chile Trench. Journal of Geophysical Research-Solid Earth and Planets. 91:471-496.   10.1029/JB091iB01p00471   AbstractWebsite

Marine geophysical data from off-shore of southern Chile are used to define the interaction between the Chile Ridge and Chile Trench during late Cenozoic time. We identify three distinct ridge-trench collision events. Between 14 and 10 Ma a 700-km-long, nearly continuous section of the Chile Ridge was sub-ducted between 55°S and 48°S. Shorter sections of the ridge, offset by large transform faults, were subducted at 6 and 3 Ma between 48°S and 47°S. At the present-day triple junction, the subduction of the ridge has a strong influence on the Chile Trench. In this region the landward trench slope has undergone a recent episode of subduction-driven tectonic erosion: the trench slope is narrower and steeper than along other sectors of the margin and the trench axis has migrated shoreward. Evidence exists for late Neogene and Quaternary uplift and plutonism on the adjacent continental margin. South of 48°S, where collision took place between 10 and 14 Ma, the effects of collision are much less pronounced. In particular, the landward trench slope does not appear to have been subjected to extensive tectonic erosion. We conclude that the configuration of the spreading centers and transform faults on the Chile Rise is the chief factor controlling ridge-trench tectonic interaction. Tectonic erosion of the landward trench slope and tectonic activity in the adjacent continental margin are much greater when short sections of ridge, offset by large transform faults, are subducted. A major sub-marine channel leads along the trench axis south-ward from the triple junction. This channel cuts across the outer trench rise and carries sediment westward to the Mornington Abyssal Plain. The Paleogene tectonic history of the southern Chile Trench includes a southward migrating, ridge-trench collision involving the Farallon-Aluk spreading center in Eocene time.

Cande, SC.  1986.  Nazca-South America plate interactions since 50 m.y.B.P.. Regional atlas series / Ocean Margin Drilling Program atlas 9, Peru-Chile trench off Peru. ( Hussong DM, Ed.)., Woods Hole, MA: Marine Science International, Abstract
Schouten, H, Cande SC, Klitgord K.  1986.  Total intensity magnetic anomalies on the Mid-Atlantic Ridge, 24°N-36°N. Regional atlas series / Ocean Margin Drilling Program atlas 12, Northwest African continental margin and adjacent ocean floor off Morocco. ( Hayes DE, Rabinowitz PD, Hinz K, Eds.)., Woods Hole, MA: Marine Science International, Abstract
LaBrecque, JL, Cande SC.  1986.  Total intensity magnetic anomaly profiles. Regional atlas series / Ocean Margin Drilling Program atlas 13, South Atlantic Ocean and adjacent Antarctic continental margin. ( LaBrecque JL, Ed.)., Woods Hole, MA: Marine Science International, Abstract
Bougault, H, Cande SC.  1985.  Background, Objectives, and Summary of Principal Results - Deep-Sea Drilling Project Sites-556-564. Initial Reports of the Deep Sea Drilling Project. 82:5-16.   10.2973/dsdp.proc.82.101.1985   AbstractWebsite
Larson, RL, Pitman III WC, Golovchenko X, Cande SC, Dewey JF, Haxby WF, Labrecque JL.  1985.  The bedrock geology of the world. , New York: W.H. Freeman and Co., Abstract
Mutter, JC, Hegarty KA, Cande SC, Weissel JK.  1985.  Breakup between Australia and Antarctica - a Brief Review in the Light of New Data. Tectonophysics. 114:255-279.   10.1016/0040-1951(85)90016-2   AbstractWebsite

The arguments justifying the revised timing of breakup between Australia and Antarctica (Cande and Mutter, 1982) and the reconstruction of Broken Ridge and Kerguelen Plateau (Mutter and Cande, 1983) are reviewed and considered with respect to new subsidence data. The age of breakup was revised from anomaly 22 time (55 My B.P.) to anomaly 34 time (85 My B.P.). The rough topography of the Diamantina Zone can be attributed to very slow spreading (−5 mm/yr.) beginning between the times of anomaly 34 and anomaly 19. The reconstruction of Broken Ridge and Kerguelen Plateau at anomaly 34 time shows overlap of these two features, but the overlap problem is nearly resolved by anomaly 18 time ( ~ 42 My B.P.). Normal seafloor spreading rates (22 mm/yr.) commenced at anomaly 19 time ( ~ 43 My B.P.). Subsidence patterns calculated from biostratigraphic data from wells drilled along Australia's southern margin are interpreted as more consistent with the revised age of Australia-Antarctic breakup. Subsidence curves systematically show rapid subsidence associated with the rift phase of margin development followed by much slower thermally-controlled subsidence during the drift phase. The timing of the rift-to-drift transition is believed to coincide with the age of breakup ( ~ 60 to 110 My B.P.). In addition, the subsidence curves indicate a west-to-east propagation of breakup along the southern margin. Magnetic anomaly patterns and stratigraphie observations are consistent with this hypothesis.

Hill, IA, Cande SC.  1985.  Downhole Logging and Laboratory Physical-Properties Measurements. Initial Reports of the Deep Sea Drilling Project. 82:351-360.   10.2973/dsdp.proc.82.114.1985   AbstractWebsite

During DSDP Leg 82 downhole logging experiments, the very poor hole conditions and technical failures that have affected earlier legs were absent. As a result, Holes 556, 558, and 564 were logged with a full suite of tools. In addition, nearly complete continuously cored sections were obtained at Sites 558 and 563, and these sections have been subjected to laboratory physical property measurements. The resulting data set allows a comparison of logged and laboratorymeasured values and correlation between holes.The sediments encountered in all holes were calcareous oozes and chalks. Despite the lack of distinctive lithologies, changes in density and seismic velocity can be seen in both the laboratory and logged data and identified with sedimentologic features in the cores; the logged curves can be correlated between holes. Within basement rocks the logged curves provide information on the part of the formations not recovered by coring (about 55%) and allow comparisonbetween bulk properties and the sample properties measured in the laboratory. Comparison of the logged data with that from Site 417 shows systematic differences, perhaps related to crustal aging.

Labrecque, JL, Cande SC, Jarrard RD.  1985.  Intermediate-Wavelength Magnetic Anomaly Field of the North Pacific and Possible Source Distributions. Journal of Geophysical Research. 90:2549-2564.   10.1029/JB090iB03p02549   AbstractWebsite

The objective of this study is to investigate the feasibility of extracting intermediate-wavelength magnetic anomalies of wavelengths between 4000 and 400 km from total field data acquired in marine magnetic surveys. The intention is to develop a second data set which may be used in conjunction with the satellite magnetic field to determine anomaly and source distributions. We apply our technique to the recovery of intermediate-wavelength total intensity anomalies over the North Pacific from marine survey data. The technique also provides a record of secular variation during the period 1960 to 1980. In areas of high track density the sea surface data can be used to refine the Magsat data processing techniques and also provide further constraints on source models. In areas of reduced sea surface track density the Magsat field provides higher resolution. The Magsat data set also records vector field data. As will be shown, the filtered sea surface data set provides a higher-resolution field than the Magsat data, due to proximity to lithospheric source bodies. The sea surface data also provide an independent check of the Magsat field, since the two fields should be equivalent after upward continuation of the sea surface field. We notice, however, that for the central Pacific the upward continued sea surface field is approximately 2 times the amplitude of the Magsat field. The spatial correlation of the two anomaly fields is very strong.

Cande, SC, Searle RC, Hill I.  1985.  Tectonic Fabric of the Seafloor near North Central Atlantic Drill Sites. Initial Reports of the Deep Sea Drilling Project. 82:17-33.   10.2973/dsdp.proc.82.102.1985   AbstractWebsite
Cande, SC, Kent DV.  1985.  Tectonic Rotations in Extensional Regimes and Their Paleomagnetic Consequences for Ocean Basalts - Comment. Journal of Geophysical Research-Solid Earth and Planets. 90:4647-4651.   10.1029/JB090iB06p04647   AbstractWebsite
Hill, IA, Cande SC.  1985.  Thermal Measurements and Seawater Downflow into 35-Ma-Old Ocean Crust, Central North-Atlantic. Initial Reports of the Deep Sea Drilling Project. 82:361-368.   10.2973/dsdp.proc.82.115.1985   AbstractWebsite

Measurements of temperature gradients in sediments, thermal conductivity and drill-hole temperatures (by wireline logging) were made in three holes drilled into basement in 35-Ma-old crust in the central North Atlantic during DSDP Leg 82. The temperature gradient and thermal conductivity values make a reliable estimate of the ambient heat flow value possible. Downhole temperatures measured by wireline logging after drilling indicate cooling of the hole in excess of that expected from the drilling process. This excess cooling effect is interpreted as a result of a substantial downflow of ocean water; a lower limit to the necessary volume of flow is derived from the data.If the downflow is a secondary effect of hydrothermal circulation within oceanic crust, these data support the increasing body of evidence that hydrothermal circulation continues within ocean crust to considerable ages covered by a blanket of sediment allowing only conductive heat flow.

Labrecque, JL, Cande SC.  1984.  Intermediate-Wavelength Magnetic-Anomalies over the Central Pacific. Journal of Geophysical Research. 89:1124-1134.   10.1029/JB089iB13p11124   AbstractWebsite

We have extracted the intermediate-wavelength magnetic anomaly field from the marine survey data of the central Pacific in the band pass of 4000–400 km (spherical harmonic degree 10–100). Our technique minimizes the effects of external field sources, secular variation, and strike aliasing. The objective of this paper is to demonstrate this capability, compare the derived sea surface field to the equivalent MAGSAT data set, and demonstrate that anomalies observed in both fields are correctable to geologic features within the oceanic lithosphere. As expected, the sea surface field exhibits a strong spatial correlation to and a better resolution than the MAGSAT field. However, the MAGSAT field also displays a diminished resolution for wavelengths less than 1900 km when compared to the upward continued sea surface data. Two reasons are likely for this diminished resolution: (1) differences in the resolution of the spherical harmonic reference fields and (2) an increased noise level in the MAGSAT data at the shorter wavelengths. Other sources of error are also considered. We also demonstrate that the remanent magnetization of the central Pacific seamounts produces negative magnetic anomalies which are observed at satellite altitude. Other sources including the thickened crust of the oceanic plateaus and regional petrologic variations can be associated with intermediate-wavelength anomalies observed in both the MAGSAT and the sea surface fields.

Rabinowitz, PD, Heirtzler JR, Cande SC.  1984.  Magnetic anomaly profiles along ship tracks. Regional atlas series / Ocean Margin Drilling Program, Eastern North American continental margin and adjacent ocean floor, 39⁰ to 46⁰ N and 54⁰ to 64⁰ W. ( Shor AN, Uchupi E, Eds.).:1atlas(3,24,a-hleaves)., Woods Hole, MA: Marine Science International Abstract
Rabinowitz, PD, Heirtzler JR, Cande SC.  1984.  Magnetic anomaly profiles along ship's tracks. Regional atlas series / Ocean Margin Drilling Program atlas 5, Eastern North American continental margin and adjacent ocean floor, 28⁰ to 36⁰ N and 70⁰ to 82⁰ W. ( Bryan GM, Heirtzler JR, Eds.)., Woods Hole, MA: Marine Science International, Abstract
Cande, SC, Heirtzler JR.  1984.  Magnetic total intensity anomalies. Regional atlas series / Ocean Margin Drilling Program, Eastern North American continental margin and adjacent ocean floor, 39⁰ to 46⁰ N and 54⁰ to 64⁰ W. ( Shor AN, Uchupi E, Eds.).:1atlas(3,24,a-hleaves)., Woods Hole, MA: Marine Science International Abstract
Heirtzler, JR, Cande SC.  1984.  Magnetic total intensity anomalies. Regional atlas series / Ocean Margin Drilling Program atlas 5, Eastern North American continental margin and adjacent ocean floor, 28⁰ to 36⁰ N and 70⁰ to 82⁰ W. ( Bryan GM, Heirtzler JR, Eds.)., Woods Hole, MA: Marine Science International, Abstract
Mutter, JC, Cande SC.  1983.  The Early Opening between Broken Ridge and Kerguelen Plateau. Earth and Planetary Science Letters. 65:369-376.   10.1016/0012-821x(83)90174-7   AbstractWebsite

Reconstructions to total closure of the Australia-Antarctic continents causes an unacceptable overlap of Broken Ridge and Kerguelen Plateau. This has been partially resolved in the past by supposing that the northern part of Kerguelen, that is principally involved in the overlap, is younger than the remainder. We have revised the early reconstructions using a newly proposed breakup chronology of Australia and Antarctica which suggests that opening began at least 90 m.y. B.P. at an initially slow rate. This eliminates the overlap problem without invoking major age differences within the Kerguelen Plateau. We also suggest that the northeastern flank of Kerguelen Plateau may be underlain by the “missing” westward continuation of the Diamantina Zone. It may have been isolated on the Antarctic plate by a ridge crest jump at about anomaly 24 time that also formed the Ob Trench.

Bougault, H, Cande S, Mills W, Curtis D, Neuser R, Christie D, Rideout M, Etoubleau J, Drake N, Brannon J, Weaver B, Echols D, Clark M, Khan MJ, Hill I.  1983.  Leg 82 of the International Program of Ocean Drilling (IPOD) - Normal or Abnormal Ocean Crust on the Mid-Atlantic Ridge - Geochemical Properties. Comptes Rendus De L Academie Des Sciences Serie Ii. 296:97-&. AbstractWebsite
Cande, SC, Herron EM, Hall BR.  1982.  The Early Cenozoic Tectonic History of the Southeast Pacific. Earth and Planetary Science Letters. 57:63-74.   10.1016/0012-821x(82)90173-x   AbstractWebsite

New marine geophysical data collected in the southeast Pacific enable us to define better the early Cenozoic tectonic history of the area and to interpret previously unexplained bathymetric features in terms of plate tectonic processes. We have identified a major re-organization in plate boundaries at anomaly 21 time when a large fragment was broken off the Pacific plate and joined to the Antarctic plate. This interpretation is based on three pieces of evidence: (1) a major ESE-trending feature, the Humboldt Fracture Zone, marks the southern boundary of the Farallon-Antarctic anomalies identified by Weissel et al. [1], (2) a north-south striking trough, the Hudson Trough, which represents the scar left by the Pacific-Antarctic Ridge when it rifted across old Pacific crust, (3) a sequence of north-south striking magnetic lineations south of the Humboldt Fracture Zone and east of the Hudson Trough is correlated to anomalies 27 to 22 and identified with Pacific-Aluk spreading.

Cande, SC, Mutter JC.  1982.  A Revised Identification of the Oldest Sea-Floor Spreading Anomalies between Australia and Antarctica. Earth and Planetary Science Letters. 58:151-160.   10.1016/0012-821x(82)90190-x   AbstractWebsite

We propose that magnetic anomalies south of Australia and along the conjugate margin of Antarctica that were originally identified as anomalies 19 to 22 may be anomalies 20 to 34. The original anomaly identification has two troublesome aspects: (1) it does not account for an “extra” anomaly between anomalies 20 and 21, and (2) it provides no explanation for the rough topography comprising the Diamantina Zone. With our revised identification there is no “extra” anomaly and the Diamantina Zone is attributed to a period of very slow spreading (∼4.5mm/yr half rate) between 90 and 43 m.y. The ages bounding the interval of slow spreading (90 and 43 m.y.) correspond to times of global plate reorganizations. Our revised identification opens up the possibility that part of the magnetic quiet zone south of Australia formed during the Cretaceous long normal polarity interval. Breakup of Australia and Antarctica probably occurred sometime between 110 and 90 m.y. B.P. The “breakup unconformity” identified by Falvey in the Otway Basin may correspond to a eustastic sea level change.