Ellins, K., and H. C. Olson, Enhancing geoscience education within a minority-serving teacher population, J. Geoscience Educ., (in press), 2012, #2465
Olson, H. C., and J. E. Damuth, Character, distribution and timing of Latest Quaternary mass-transport deposits in Texas-Louisiana interslope basins based on high-resolution (3.5 kHz) seismic facies and piston cores, in Submarine Mass Movements and Their Consequences, edited by D. C. Mosher, L. Moscardelli, R. C. Shipp, J. D. Chaytor, C. P. D. Baxter, H. J. Lee, and R. Urgeles, Advances in Natural and Technological Hazards Research, 607-617, 2010, #2312
Goff, J. A., J. A. Austin, S. P. S. Gulick, S. Nordfjord, B. Christensen, C. K. Sommerfield, H. C. Olson, and C. R. Alexander, Recent and modern marine erosion on the New Jersey outer shelf, Marine Geol., 216, 275-296, 2005, 22 citations, doi:10.1016/j.margeo.2005.02.015, #1756
Goff, J. A., L. A. Mayer, P. Traykovski, I. Buynevich, R. H. Wilkens, R. Raymond, G. Glang, R. L. Evans, H. C. Olson, and C. Jenkins, Detailed investigation of sorted bedforms, or 'rippled scour depressions', within the Martha's Vineyard Coastal Observatory, Massachusetts, Continental Shelf Res., 25, 461-484, 2005, 32 citations, doi:10.1016/j.csr.2004.09.019, #1876 
We examine in detail the seafloor and cross-sectional morphology of sorted bedforms (i.e., ârippled scour depressionsâ) in the Martha's Vineyard Coastal Observatory (MVCO). Sorted bedforms are seen as alternating bands of coarse and fine sands oriented nearly perpendicular to the shoreline. The coarse sand zones (CSZs) of the sorted bedforms are tens to hundreds of meters wide, and extend up to several kilometers from the shoreface. Data considered here include time series of swath backscatter and bathymetry, high resolution chirp seismic reflection, and grain-size analyses from grab samples, vibracores and push cores. The sorted bedforms observed within the MVCO survey area exhibit a broad spectrum of bathymetric relief (from 10 cm to 3 m), grain-size contrast (from 250 to>2000 μm) and morphologic form (moats, steps, and dune forms). All forms observed display lateral asymmetry in both grain size and bathymetric expression. In general, grain size is largest and bathymetry is deepest toward one side, typically seen in the backscatter maps as the more well defined of the two CSZ edges where that distinction can be made. These observations are consistent with earlier studies suggesting that sorted bedforms are a response to a transverse, alongshore flow. Within the MVCO survey area, the sense of asymmetry changes polarity going from west/shallow water to east/deeper water, suggesting a complex hydrographic regime.
Olson, H. C., and P. R. Thompson, Sequence biostratigraphy with examples from the Plio-Pleistocene and Quaternary, in Applied Stratigraphy, edited by E. A. M. Koutsoukos, Kluwer Acad. Pub., 227-247, 2005, #1553
Goff, J. A., B. J. Kraft, L. A. Mayer, S. G. Schock, C. K. Sommerfield, H. C. Olson, S. P. S. Gulick, and S. Nordfjord, Seabed characterization on the New Jersey middle and outer shelf: Correlatability and spatial variability of seafloor sediment properties, Marine Geol., 209, 147-172, 2004, 55 citations, doi:10.1016/j.margeo.2004.05.030, #1689
Nearly 100 collocated grab samples and in situ 65 kHz acoustic measurements were collected on the New Jersey middle and outer shelf within an area that had previously been mapped with multibeam backscatter and bathymetry data, and more recently with chirp seismic reflection profiling. Eighteen short cores were also collected and probed for resistivity-based porosity measurements. The combined data set provides a basis for empirically exploring the relationship among the remotely sensed data, such as backscatter and reflection coefficients, and directly measured seabed properties such as grain size distribution, velocity, attenuation and porosity. We also investigate the spatial variability of these properties through semi-variogram analysis to facilitate acoustic modeling of natural environmental variability.
Grain size distributions on the New Jersey shelf are commonly multi-modal, leading us to separately characterize coarse % (>4 mm), fine % (<63 μm) and mean sand grain size to quantify the distribution. We find that the backscatter is dominated by the coarse component (expressed as weight %), typically shell hash and occasionally terrigenous gravel. In sediment types where coarse material is not significant, backscatter correlates with velocity and fine weight %. Mean sand grain size and fine % are partially correlated with each other, and combined represent the primary control on velocity. The fine %, rather than mean grain size as a whole, appears to be the primary control on attenuation, although coarse % may increase attenuation marginally through scattering. Vertical-incidence seismic reflection coefficients, carefully culled of unreliable values, exhibit a strong correlation with the in situ velocity measurements, suggesting that such data may prove more reliable than backscatter at deriving sediment physical properties from remote sensing data. The velocity and mean sand grain size semi-variograms can be fitted with a von Kármán statistical model with horizontal scale 12.6 km, which provides a basis for generating synthetic realizations. The backscatter and coarse % semi-variograms exhibit two horizontal scales: one 8 km and the other too small to quantify with available data.
Olson, H. C., and C. W. Smart, Pleistocene climatic history reflected in planktonic foraminifera from ODP Site 1073 (Leg 174A), New Jersey margin, NW Atlantic Ocean, Marine Micropaleontology, 51, 213-238, 2004, 3 citations, doi:10.1016/j.marmicro.2003.11.002, #1658
Abundance records of planktonic foraminifera (>150 μm) from the upper 520 m of ODP Site 1073 (Hole 1073A, Leg 174A, 639 m water depth) have been integrated with SPECMAP-derived isotope stratigraphy, percentage of calcium carbonate, and coarse sediment fraction data in order to investigate the Pleistocene climatic history of the New Jersey margin. Six planktonic taxonomic groups dominate the foraminiferal assemblage at Site 1073: Neogloboquadrina pachyderma (d) (mean 33.8%), Turborotalita quinqueloba (18.5%), N. pachyderma (s) (18.4%), Globigerina bulloides group (11.4%), Globorotalia inflata group (9.4%), and Globigerinita glutinata (4.1%). Based on the distributions of these six foraminiferal groups, the Pleistocene section can be divided into three paleoclimatic intervals: Interval I (intermediate) corresponds to the Quaternary sediments from sequence boundary pp1 to the seafloor (79.5â0 mbsf; Emiliania huxleyi acme [85 ka] at 72 mbsf); Interval II (warm) occurs between sequence boundaries pp3 and pp1 (325â79.5 mbsf; last occurrence of Pseudoemiliania lacunosa [460 ka] at 330 mbsf); and Interval III (coldest) occurs between sequence boundaries pp4 and pp3 (520â325 mbsf; Calcareous nannofossils and dinocysts in proximity to pp4 indicate that the sedimentary record for 0.9â1.7 Ma is either missing altogether or highly condensed within the basal few meters of the section).
Neogloboquadrina pachyderma (d) displays eight peaks of abundance which correlate, for the most part, with depleted δ18O values, increases in calcium carbonate percentages, low coarse fraction percentages, increased planktonic fragmentation (greater dissolution), and low N. pachyderma (s) abundances. These intervals are interpreted as representing warmer/interglacial conditions.
Neogloboquadrina pachyderma (s) displays seven peaks of abundance which correlate, for the most part, with δ18O increases, decreases in calcium carbonate percentages, increases in coarse fraction percentages, and low N. pachyderma (d) abundances. These intervals are interpreted as representing cooler/glacial conditions.
In Interval III, a faunal response to relative changes in sea-surface temperature is reflected by abundance peaks inNeogloboquadrina pachyderma (d), followed by Turborotalita quinqueloba and then N. pachyderma (s) (proceeding from warmest to coolest, respectively). This tripartite response is consistent with the oxygen isotope record and, although not as clear, also occurs in Intervals I and II.
Six peaks/peak intervals of Globigerina bulloides abundance are closely matched by peaks in Globigerinita glutinata and occur within oxygen isotope stage (OIS) 2 (latter part) 3, 4, 5, 8, 9, 13(?), 14(?), and 15(?). We speculate that these intervals reflect increased upwelling and nutrient levels during both glacials and interglacials. Eight peak intervals of Globorotalia inflata show a general inverse correlation with G. bulloides and may reflect lowered nutrient and warmer surface waters.
Leckie, R. M., and H. C. Olson, Foramnifera as proxies of sea-level change on siliciclastic margins, in Micropaleontological Proxies for Sea-Level Change and Stratagraphic Discontinuities, edited by H. C. Olson and R. M. Leckie, SEPM Spec. Publ., 75, 5-20, 2003, #1588
Olson, H. C., A. Gary, and G. Jones, Similarity curves as indicators of stratigraphic discontinuities, in Micropaleontological Proxies for Sea-Level Changes and Stratagraphic Discontinuities, edited by H. C. Olson and R. M. Leckie, SEPM spec. publ., 75, 89-96, 2003, #1550
Olson, H. C., and R. M. Leckie, Preface: Micropaleontologic proxies for sea-level change and stratagragraphic discontinuities, in Micropaleontological Proxies for Sea-Level Change and Stratagraphic Discontinuities, edited by H. C. Olson and R. M. Leckie, SEPM Spec. Publ., 75, 1-4, 2003, #1659
Olson, H. C., and R. M. Leckie, (Editors), Micropaleontological Proxies for Sea-Level Change and Stratigraphic Discontinuities, SEPM Spec. Publ., 75, 383 pp., 2003, #1677
McHugh, C. M. G., and H. C. Olson, Pleistocene chronology of continental margin sedimentation: New insights into traditional models, New Jersey, Marine Geol., 186, 389-411, 2002, 23 citations, doi:10.1016/S0025-3227(02)00198-6, #1552
Commonly accepted models for the evolution of continental margins link sediment erosion, transport and deposition to eustasy. To test these models, we constructed an oxygen isotope record from 520 m of Pleistocene sediment recovered by the Ocean Drilling Program Leg 174A from the New Jersey continental slope. The δ18O record was calibrated to SPECMAP oxygen isotope time scale [Imbrie et al. (1984), in: Berger et al. (Eds.), Milankovitch and Climate, 269â305] with radiocarbon ages, nannoplankton biostratigraphy, magnetostratigraphy, and opal and calcium carbonate stratigraphy. Sixteen glacial/interglacial fluctuations of global ice volume have been recorded in the Pleistocene: oxygen isotope stages (OIS) 1 (partial), 2â4, 5 (partial) and 8 throughout 18. Contrary to predicted sedimentation models, a classification of mass-wasting deposits, based on variations in the styles of soft-sediment deformation and grain size, shows that: (1) mass-wasting is not restricted to glacial times but is present during both glacial and interglacial stages; (2) glacial stages are dominated by fine-grained sediments some of which were deposited by gravity flows; and (3) the transitions from glacial to interglacial stages are characterized by the deposition of coarse sands. The sedimentary record shows large-scale trends that do not fit the traditional models of higher glacial sedimentation rates since there is no consistent variation in sediment accumulation between glacial and interglacial stages. Instead there are longer-term sedimentation patterns. Uniform sedimentation rates of 62 cm/kyr characterize the early middle Pleistocene (OIS 12â18), followed by varying rates from low to very high for three consecutive time periods: OIS 11 to 9 (98â560 cm/kyr), OIS 8 (52â560 cm/kyr), and OIS 5 to 2 (37â353 cm/kyr). Each of these depositional units is contained within one seismic-stratigraphic sequence and bounded by sequence boundaries. Their deposition was influenced by the supply of sediment rather than eustasy. Sediment supply was modulated by: (1) the transition from the dominance of obliquity to that of eccentricity (OIS 18â12 to OIS 11â1); and (2) the proximity of the ice sheet (located 150 km away from the paleoshoreline during the last glacial maximum).
Damuth, J. E., and H. C. Olson, Neogene-Quaternary contourite and related deposition on the West Shetland Slope and Faeroe-Shetland channel revealed by high-resolution seismic studies, Marine Geophysical Researches, 22, 369-399, 2001, 9 citations, doi:10.1023/A:1016395515456, #1620
The Neogene and Quaternary sediments of the Faeroe-Shetland Channel and West Shetland shelf and slope rest upon a major regional unconformity, the Latest Oligocene Unconformity (LOU), and have been deposited through the interaction of downslope and parallel-to-slope depositional processes. The upper to middle continental slope is dominated by mass-transport deposits (debris flows), which progressively diminish downslope, and were largely generated and deposited during glacial cycles when ice sheets supplied large quantities of terrigeneous sediment to the upper slope and icebergs scoured sea-floor sediments on the outer shelf and uppermost slope. Large-scale sediment failures have also occurred on the upper slope and resulted in deposition of thick, regionally extensive mass-transport deposits on portions of the lower slope and channel floor. In contrast, large fields of migrating sediment waves and drift deposits dominate most of the middle to lower slope below 700 m water depth and represent deposition by strong contour currents of the various water masses moving northeastward and southwestward through the channel. These migrating sediment waves indicate strong northeastward current flow at water depths shallower than 700 m and strong southwestward current flow at water depths from 700 to >1,400 m. These flow directions are consistent with present-day water-mass flow through the Faeroe-Shetland Channel. The Faeroe-Shetland Channel floor is underlain by thin conformable sediments that appear to be predominantly glacial marine and hemipelagic with less common turbidites and debris flows. No evidence is observed in seismic or core data that indicates strong contour-current erosion or redistribution of sediments along the channel floor.
Savrda, C. E., H. Krawinkel, F. M. G. McCarthy, C. M. G. McHugh, H. C. Olson, and G. S. Mountain, Ichnofabrics of a Pleistocene slope succession, New Jersey margin: Relations to climate and sea-level dynamcs, Palaeogeography, Palaeoclimatology, Palaeoecology, 171, 41-61, 2001, 20 citations, doi:10.1016/S0031-0182(01)00266-8, #1551
Trace fossil and sedimentologic data were collected at 10 cm intervals throughout a virtually continuous, 520 m-thick Upper Pleistocene siliciclastic succession recovered at ODP Site 1073 (New Jersey margin). These data were examined in the context of isotopic, seismic, and palynologic proxies to document depositional and ichnologic responses to Quaternary climate and sea-level dynamics in an upper slope setting. Two broad, texturally defined sedimentary facies assemblages are recognized. The clay-rich assemblage reflects relatively rapid deposition, in part from turbidity currents and suspended plumes, and appears to be linked to cooler, sea-level fall and lowstand phases. The sand-rich assemblage reflects overall slower sedimentation by offshelf spillover and periodic winnowing and erosion, under the influence of contour and other bottom currents, during warmer transgressive/highstand phases. Facies of the sand-rich assemblage (muds, sandy muds, muddy sands, and sands) are completely bioturbated and are characterized by high densities of biogenic structures, including distinct burrow forms. In contrast, the clay-rich assemblage includes facies that exhibit limited biogenic disruption (laminated clay/silty clay and graded silt- or fine sand-to-clay couplets) and, on the whole, is characterized by lower densities of biogenic structures, most of which are diffuse burrow mottles. These ichnofabric trends reflect changes in ecological and taphonomic parameters (e.g. substrate stability and consistency, residence time of sediments in the benthic boundary layer, and degree of inter- and intrabed textural variability), many of which were governed by variations in sedimentation rate as mediated by glacio-eustacy. Recurring, identifiable ichnofossils are most common in facies of the sand-rich assemblage in the upper half of the Pleistocene succession. Finer-grained components of this assemblage (e.g. muds and sandy muds), representing quieter phases of highstand deposition, are characterized by a low-diversity distal Cruziana ichnofacies assemblage dominated by Schaubcylindrichnus and Phycosiphon (=Anconichnus), both of which represent the work of deposit-feeding worms. Narrow facies transitions that correspond to phases of rapid transgression are marked by occurrences of Thalassinoides. These crustacean burrow systems were excavated in coarser-grained, higher-energy facies (sands and muddy sands) and in closely associated firmground substrates produced by exhumation of consolidated muds by bottom currents and/or mass-wasting processes. The association of firmground ichnofabrics with marine flooding events in an upper slope setting demonstrates that the sequence stratigraphic utility of the Glossifungites ichnofacies extends beyond shelf depositional sequences to deeper-water deposits. The distribution of texturally defined facies and general ichnofabric parameters (e.g. degree of bioturbation) appears to respond to glacio-eustatic cycles through the entire Pleistocene record. However, the SchaubcylindrichnusâPhycosiphon assemblage and Thalassinoides are rare or absent altogether in the lower half of the succession, indicating that biological responses to, and the ichnologic record of, climate and sea-level dynamics may be strongly dependent on margin physiographic and bathymetric evolution.
Goff, J. A., H. C. Olson, and C. S. Duncan, Correlation of side-scan backscatter intensity with grain-size distribution of shelf sediments, New Jersey margin, Geo-Marine Lett., 20, 43-49, 2000, 40 citations, doi:10.1007/s003670000032, #1499
The dependence of acoustic backscatter variations on sediment grain-size distribution is examined using a combined analysis of 95 kHz side-scan data and approx. 300 grab samples from the New Jersey margin. We show that, under well-controlled circumstances, an unprecedented degree of correlation can be obtained between backscatter intensity and mean grain size. However, backscatter is disproportionately affected by larger grain sizes. Addition of just a few extra weight percentage of the larger grain sizes (>4 mm), which in our study is typically represented by more abundant shell hash among the older sediments at greater water depths, can completely degrade this correlation.
Olson, H. C., J. E. Damuth, P. E. Ganey-Curry, and G. D. Moss, Intraslope basins reveal US Gulf of Mexico secrets, Offshore, 60 (6), 112-114, 2000, #1531
Buck, K. F., H. C. Olson, and J. A. Austin, Paleoenvironmental evidence for latest Pleistocene sea-level fluctuations on the New Jersey outer continental shelf: Combining high-resolution sequence stratigraphy and foraminiferal analysis, Marine Geol., 154, 287-304, 1999, 21 citations, doi:10.1016/S0025-3227(98)00119-4, #1303
Foraminiferal assemblages in vibracored sediments within 5 m of the seafloor document high-resolution sea-level fluctuations and confirm the complex Quaternary depositional history of the New Jersey margin. Biostratigraphic data have been integrated with ongoing 2-D/3-D high-resolution seismic analyses to interpret paleoenvironments of surficial stratigraphy beneath the modern middle-to-outer shelf. Cluster analysis of foraminiferal assemblages sampled every 20 cm (average) define four sample groups (AâD) dominated by benthic species. Group A, characterized by Cibicides lobatulus, is a middle-to-outer-shelf assemblage (60â100 m water depths). Group B is composed of middle-shelf species (30â60 m water depths) and is characterized by low abundances and a fairly uniform distribution of foraminifera, which suggests reworking and/or a high rate of sediment accumulation. Group C, dominated by Elphidium excavatum, is an inner-to-middle-shelf assemblage (10â40 m water depths). Group D, present in only one core and dominated by Ammonia beccarii, represents marginal marine environments (0â10 m water depths, with fluctuations in salinity). In general, the modern sedimentary veneer (i.e., the upper 20 cm) is characterized by the deeper-water fauna of group A. Sediments below these modern deposits are characterized by groups B and C, reflecting shallower water depths and variable sediment-accumulation rates on the inner and middle shelf. Taken together, the group succession in the cores suggests an overall SE-to-NW (landward) transgression in these latest PleistoceneâHolocene deposits. Seismic analysis indicates that one core (27) penetrates the flank of a buried channel, including its fill and the pre-channel section. Within the channel, three alternations of groups C and D suggest fluctuations between marginal-marine and middle-shelf paleoenvironments; high-frequency, perhaps very small (<10 m?) changes in base level are indicated. Using previously published AMS 14C dates, these fluctuations can be constrained as having occurred between 45,000 yr B.P. (channel incision) and 12,500 yr B.P. (channel filling), suggesting the non-uniform nature of the last Wisconsinan deglaciation.
Marsaglia, K. M., P. Mann, R. J. Hyatt, and H. C. Olson, Evaluating the influence of aseismic ridge subduction and accretion(?) on the detrital modes of forearc sandstone: An example from the Kronotsky Peninsula in the Kamchatka forearc, Lithos, 46, 17-42, 1999, 5 citations, doi:10.1016/S0024-4937(98)00054-1, #1388
The Kronotsky Peninsula, in the forearc region of the Kamchatka magmatic arc, lies on trend with the Emperor Seamount chain situated on the currently subducting Pacific tectonic plate. Detrital modes of volcaniclastic sandstone interbedded with mafic Eocene(?) basement rocks and within the overlying sedimentary sequence provide insight into the late Cenozoic geologic history of this area. Eocene(?) and basal Miocene sandstones are primarily composed of variably altered mafic volcanic debris. Their detrital modes are similar to those of Emperor Seamount sandstones and Hawaiian beach sands. Although aspects of the stratigraphy and volcaniclastic sand composition are consistent with a seamount setting, there is no physical evidence for an accretion event, and the suggested Eocene age for this unit makes an Emperor Seamount origin unlikely. A seamount origin cannot be ruled out for older Kronotsky basement complexes, however. A Miocene lull in Kronotsky volcanism was followed by rapid basin subsidence and influx of arc-derived turbidites from the west. Detrital modes of these sandstones are typical of a moderately evolved continental or micro-continental arc. An anomalously high proportion of sedimentary lithic fragments is the only possible compositional fingerprint attributable to seamount or ridge subduction.
Lagoe, M. B., T. A. Davies, J. A. Austin, and H. C. Olson, Foraminiferal constraints on very high-resolution seismic stratigraphy and Late Quaternary glacial history, New Jersey continental shelf, Palaios, 12, 249-266, 1997, 17 citations, #1225