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- Keyword
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- 12 Stratigraphy (3)
- 06 Petrology (1)
- 07 Marine Geology and Oceanography Calcareous composition; carbonate rocks; chalk; clastic sediments; density; Leg 130; marine sediments; Ocean Drilling Program; Ontong Java Plateau; ooze; Pacific Ocean; physical properties; porosity; sedimentary rocks; sediments; West Pacific (1)
- 07 Marine Geology and Oceanography; 20 Geophysics (1)
- Applied Anisotropy; biogenic structures; bioturbation; body waves; calcareous composition; carbonate rocks; chalk; clastic sediments; elastic waves; Leg 130; measurement; Ocean Drilling Program; Ontong Java Plateau; ooze; P-waves; Pacific Ocean; sedimentary rocks; sedimentary structures; sediments; seismic waves; transition zones; velocity; West Pacific (1)
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- Applied Carbonate rocks; deep-water environment; density; geophysical methods; Leg 130; Ocean Drilling Program; Ontong Java Plateau; Pacific Ocean; paleo-oceanography; physical properties; plateaus; reflection methods; sedimentary rocks; sedimentation; seismic stratigraphy; seismograms; synthetic seismograms; velocity; well-logging; West Pacific (1)
- Data Visualization (1)
- Geophysics (1)
- Historical Geology and Paleoecology Biostratigraphy; Cenozoic; correlation; Leg 130; Neogene; Ocean Drilling Program; Ontong Java Plateau; Pacific Ocean; physical properties; sedimentary rocks; sedimentation; sedimentation rates; stratigraphy; Tertiary; well-logging; West Pacific (1)
- Historical Geology and Paleoecology Biostratigraphy; Cenozoic; cycles; gamma-ray attenuation porosity evaluator; glacial environment; GRAPE; Leg 130; Milankovitch theory; Neogene; Ocean Drilling Program; ODP Site 806; Ontong Java Plateau; Pacific Ocean; paleoclimatology; Pliocene; Quaternary; statistical analysis; Tertiary; time series analysis; West Pacific N001906 N001907 E1592142 E1592140 (1)
- Historical Geology and Paleoecology; 02 Geochemistry Cenozoic; climate effects; cycles; evolution; Foraminifera; glaciation; ice; Invertebrata; isotope ratios; isotopes; Leg 130; microfossils; Neogene; O-18/O-16; Ocean Drilling Program; ODP Site 806; Ontong Java Plateau; oxygen; Pacific Ocean; planktonic taxa; Pliocene; Protista; stable isotopes; Tertiary; West Pacific N001906 N001907 E1592142 E1592140 (1)
- Historical Geology and Paleoecology; 20 Geophysics (1)
- Igneous and Metamorphic Basalts; basement; Cretaceous; geophysical methods; geophysical surveys; igneous rocks; lava; Leg 130; Mesozoic; Ocean Drilling Program; Ontong Java Plateau; Pacific Ocean; pillow lava; reflection methods; seismic methods; surveys; volcanic features; volcanic rocks; West Pacific (1)
- Sedimentary; 12 Stratigraphy (1)
- Solid-Earth; 05 Petrology (1)
Articles 1 - 11 of 11
Full-Text Articles in Physical Sciences and Mathematics
Visualizing Object Oriented Software In Three Dimensions, Colin Ware, David Hui, Glenn Franck
Visualizing Object Oriented Software In Three Dimensions, Colin Ware, David Hui, Glenn Franck
Center for Coastal and Ocean Mapping
There is increasing evidence that it is possible to perceive and understand increasingly comple x information systems if they are displayed a s graphical objects in a three dimensional space . Object-oriented software provides an interestin g test case - there is a natural mapping fro m software objects to visual objects . In this paper we explore two areas. 1) Information perception : we are running controlled experiments to determine empirically if our initial premise is valid; how much more (or less) can be understoo d in 3D than in 2D? 2) Layout: our strategy is to combine partially …
Acoustic Properties Of Fine‐Grained Sediments From Emerald Basin: Toward An Inversion For Physical Properties Using The Biot–Stoll Model, Robert C. Courtney, Larry A. Mayer
Acoustic Properties Of Fine‐Grained Sediments From Emerald Basin: Toward An Inversion For Physical Properties Using The Biot–Stoll Model, Robert C. Courtney, Larry A. Mayer
Affiliate Scholarship
Acoustic data from two long cores, comprising marine clays and silts taken from Emerald Basin off Nova Scotia, are presented. High‐resolution measurements of compressional wavevelocity,attenuation, and power law exponent are made using ultrasonic frequencies between 100 to 1000 kHz. The observed values of the frequency dependence of attenuation suggest that a nonconstant Q mechanism is needed to explain these data, and Biot–Stoll theory is used to model the experimental results. An inversion scheme is used to constrain physical parameters in the Biot–Stoll dispersion relation. The inversion shows that there is a restricted range of permeability and grain size. By assigning …
Calculation Of Acoustic Parameters By A Filter-Correlation Method, Robert C. Courtney, Larry A. Mayer
Calculation Of Acoustic Parameters By A Filter-Correlation Method, Robert C. Courtney, Larry A. Mayer
Affiliate Scholarship
This paper presents the filter correlation method, a technique for extracting consistent and accurate estimates of attenuation parameters from acoustic waveform data. The method minimizes problems associated with short time windows and multipath secondary arrivals. The method comprises two stages: a causal passband filter stage followed by a cross-correlation step. The results of the filter-correlation estimator are compared to those of the spectral difference approach for short time series with and without a secondary multipath arrival. Preliminary analyses of acoustic data collected on cored marine silts and clays show the attenuation properties of these materials cannot be described by a …
Laboratory And Well-Log Velocity And Density Measurements From The Ontong Java Plateau: New In-Situ Corrections To Laboratory Data For Pelagic Carbonates, Jozsef Urmos, Roy H. Wilkens, Frank Bassinot, Mitchell Lyle, Janice C. Masters, Larry A. Mayer, David Mosher
Laboratory And Well-Log Velocity And Density Measurements From The Ontong Java Plateau: New In-Situ Corrections To Laboratory Data For Pelagic Carbonates, Jozsef Urmos, Roy H. Wilkens, Frank Bassinot, Mitchell Lyle, Janice C. Masters, Larry A. Mayer, David Mosher
Affiliate Scholarship
During Ocean Drilling Program Leg 130, sonic velocity and bulk density/porosity well logs were measured in five separate holes drilled through the sequence of pelagic carbonate oozes, chalks, and limestones that comprise the thick, continuous sedimentary cover on the Ontong Java Plateau. An internally consistent and continuous suite of shipboard laboratory velocity and sediment physical properties measurements were made from the top of each hole down through the entire logged interval. Because of the high quality of the data, extensive overlap of 500 m or more between the log and laboratory measurements at each hole, and the homogeneous nature of …
Evolution Of Pliocene Climate Cyclicity At Hole 806b (5-2 Ma); Oxygen Isotope Record, Eystein Jansen, Larry A. Mayer, Jan Backman, R. Mark Leckie, Toshiaki Takayama
Evolution Of Pliocene Climate Cyclicity At Hole 806b (5-2 Ma); Oxygen Isotope Record, Eystein Jansen, Larry A. Mayer, Jan Backman, R. Mark Leckie, Toshiaki Takayama
Affiliate Scholarship
A detailed Pliocene oxygen isotope record from the Ontong Java Plateau, based on measurements of the surface-dwelling planktonic foraminifer Globigerinoides sacculifer, was produced for the period from 5 to 2 Ma. The record documents major long and short-term climate changes. The results show periods of enhanced ice volume at 4.6 to 4.3 Ma and after 2.85 Ma, a long-term warming trend from 4.1 to 3.7 Ma, and a distinct cooling trend that was initiated at 3.5 Ma and progressed through the initiation of large-scale Northern Hemisphere glaciation after 2.85 Ma (according to the time scale of Shackleton and others proposed …
Seismic Stratigraphy Of The Ontong Java Plateau, David Mosher, Larry A. Mayer, Tom H. Shipley, Edward L. Winterer, Rick A. Hagen, Janice C. Marsters, Frank Bassinot, Roy H. Wilkens, Mitchell Lyle
Seismic Stratigraphy Of The Ontong Java Plateau, David Mosher, Larry A. Mayer, Tom H. Shipley, Edward L. Winterer, Rick A. Hagen, Janice C. Marsters, Frank Bassinot, Roy H. Wilkens, Mitchell Lyle
Affiliate Scholarship
The Ontong Java Plateau, a large, deep-water carbonate plateau in the western equatorial Pacific, is an ideal location for studying responses of carbonate sedimentation to the effects of changing paleoceanographic conditions. These carbonate responses are often reflected in the physical properties of the sediment, which in turn control the appearance of seismic reflection profiles. Seismic stratigraphy analyses, correlating eight reflector horizons to each drill site, have been conducted in an attempt to map stratigraphic data. Accurate correlation of seismic stratigraphic data to drilling results requires conversion of traveltime to depth in meters. Synthetic seismogram models, using shipboard physical properties data, …
Velocity Anisotropy In Calcareous Sediments From Leg 130, Ontong Java Plateau, Frank Bassinot, Janice C. Marsters, Larry A. Mayer, Roy H. Wilkens
Velocity Anisotropy In Calcareous Sediments From Leg 130, Ontong Java Plateau, Frank Bassinot, Janice C. Marsters, Larry A. Mayer, Roy H. Wilkens
Affiliate Scholarship
During Leg 130, an intensive program of P-wave velocity measurements was conducted on calcareous sediments of varying induration (ranging from ooze to limestone) that cover the Ontong Java Plateau (west equatorial Pacific). The high quantity and quality of shipboard acoustical property measurements seemed to be particularly appropriate for gaining a better understanding of acoustic anisotropy in calcareous sediments. Major results can be summarized as follows: 1. In calcareous oozes, acoustic anisotropy exists even at shallow depths of burial. Values are low, ranging from -0.5% to 3.5% and averaging 1.2%. Anisotropy profiles are affected by coring disturbances, but they still roughly …
Climatic Cyclicity At Site 806; The Grape Record, Larry A. Mayer, Eystein Jansen, Jan Backman, Toshiaki Takayama
Climatic Cyclicity At Site 806; The Grape Record, Larry A. Mayer, Eystein Jansen, Jan Backman, Toshiaki Takayama
Affiliate Scholarship
We used the continuous saturated bulk density records collected by the gamma-ray attenuation porosity evaluator (GRAPE) at Ocean Drilling Program Site 806 on the top of the Ontong Java Plateau to evaluate the continuity of the recovered cores and to splice together a complete section from the multiple holes drilled at the site (for the upper 165 m, this is equivalent to approximately 0-5 Ma). The lack of offset in core breaks (between the 9.5-m-long, successive cores) from hole to hole made splicing difficult, and the results are not unambiguous. The composite section was converted to a time series by …
Variations Of Porosity In Calcareous Sediments From The Ontong Java Plateau, Frank Bassinot, Janice C. Marsters, Larry A. Mayer, Roy H. Wilkens
Variations Of Porosity In Calcareous Sediments From The Ontong Java Plateau, Frank Bassinot, Janice C. Marsters, Larry A. Mayer, Roy H. Wilkens
Affiliate Scholarship
Based on index properties measurements made on board the JOIDES Resolution, we studied porosity changes with depth in the fairly homogeneous deep-sea calcareous sediments cored during Ocean Drilling Program Leg 130 on the Ontong Java Plateau. Using Leg 130 data, we present evidence that the rate of porosity decrease with burial in calcareous oozes and chalks is related to the depth of deposition and thus probably depends on the "conditioning" of calcareous sediments by winnowing or dissolution processes during the time of deposition. The ooze-to-chalk transition is not clearly reflected in porosity profiles. In the ooze-chalk sections studied (the upper …
Basement Structure Of The Northern Ontong Java Plateau, Rick A. Hagen, Larry A. Mayer, David Mosher, Loren W. Kroenke, Tom H. Shipley, Edward L. Winterer
Basement Structure Of The Northern Ontong Java Plateau, Rick A. Hagen, Larry A. Mayer, David Mosher, Loren W. Kroenke, Tom H. Shipley, Edward L. Winterer
Affiliate Scholarship
Site surveys conducted in conjunction with Leg 130 on the Ontong Java Plateau reveal a strong seismic reflector at 0.8 to 1.0 s below the seafloor that drilling at Sites 803 and 807 confirmed is Cretaceous basalt. This reflector is generally smooth, except for the northeastern margin of the plateau, where it forms a series of small, irregularly shaped depressions. Correlatable reflectors present at the bottom of the depressions are also present on the adjacent highs, suggesting that these depressions are original volcanic topography. A strong sub-basalt reflector occurs on many seismic profiles on the northeastern portion of the plateau. …
Detailed Stratigraphic Correlation Of The Neogene Sedimentary Sequences On The Ontong Java Plateau By Well Logging; Odp Sites 803, 805, 806, 807, And Dsdp Site 586, Mitchell Lyle, Roy H. Wilkens, Larry A. Mayer
Detailed Stratigraphic Correlation Of The Neogene Sedimentary Sequences On The Ontong Java Plateau By Well Logging; Odp Sites 803, 805, 806, 807, And Dsdp Site 586, Mitchell Lyle, Roy H. Wilkens, Larry A. Mayer
Affiliate Scholarship
We used well logs, in some cases combined with shipboard physical properties measurements to make more complete profiles and to correlate between sites on the Ontong Java Plateau. By comparing sediment bulk density, velocity, and resistivity logs from adjacent holes at the same site, we showed that even subtle features of the well logs are reproducible and are caused by variations in sedimentation. With only minor amounts of biostratigraphic information, we could readily correlate these sedimentary features across the entire top of the Ontong Java Plateau, demonstrating that for most of the Neogene the top of the plateau is a …