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Identified and dated New Jersey sequences
Results and publications from this research.
Correlated NJ Oligocene sequences to the oxygen isotope records
and the Haq et al. eustatic record (1987)
Early to middle Miocene sequences in New Jersey were identified
Correlated the NJ Oligocene sequences to other records
Identified two new Oligocene formations
Developed a method to estimate eustatic
change and implemented it for the Oligocene
Results and publications from this research.
Reconstructed the stratal geometry of Oligocene strata in
New Jersey
Water depths were determined for continental margin in New
Jersey for Oligocene strata
Estimated global sea-level changes between 34 and 23 Ma
Evaluated the stratigraphic response on passive margins to
global sea-level changes
Global sea-level changes were calibrated to oxygen isotope
records
Quantitatively evaluated the factors that control sedimentation
on passive margins
Developed a new high-resolution chrono-stratigraphic
tool to date Albian strata in West Africa: Sr-chemostratigraphy
Identified and dated Miocene sequences in
offshore West Africa using an integrated approach
Identified and dated New Jersey Oligocene
sequences
Oligocene sequences from sediments obtained
from boreholes drilled as part of the onshore Ocean Drilling
Program Leg 150X were identified and dated.
September, 1993 - May, 1996
Rutgers University
I was a member of a team investigating cores drilled as part
of the onshore component of the Ocean Drilling Program Legs
150X and 174AX. I took the lead on the Oligocene studies,
by integrating lithostratigraphy, benthic foraminiferal biofacies,
planktonic foraminiferal biostratigraphy, seismic stratigraphy,
and Sr-isotopic chemostratigraphy with studies from other
researchers (such as magnetostratigraphy and calcareous nannofossil
biostratigraphy). Eight major Oligocene unconformities were
identified from this research. Benthic foraminiferal biofacies
studies helped define unconformities and give evidence for
the magnitude of sea-level change both within and between
sequences.
Results and publications from this research.
Eight Oligocene sequences and the
systems tracts within them were identified on the New Jersey
coastal plain.
This was the first time that detailed sequence stratigraphy
had been accomplished for New Jersey Oligocene strata. Relative
water depths for the benthic foraminiferal biofacies were
also estimated.
Publication:
Pekar, S. F., Miller, K. G., and
Olsson R. K., 1997, New Jersey coastal plain Oligocene sequences,
ODP Leg 150X: in Miller, K. G. and Snyder, S. W., Proceedings
Ocean Drilling Program, Scientific Results, 150X: College,
Texas (Ocean Drilling Program), p. 187-206.
Abstracts:
Pekar, S. F., and Miller, K. G.,
1995, New Jersey Oligocene recorded at the Leg 150X borehole
sites (at Cape May, Atlantic City, Island Beach): The First
SEPM Congress on Sedimentary Geology, Aug. 13-16, p. 99.
Pekar, S. F., and Miller, K. G., 1995, New Jersey Oligocene
sequences: eustatics and tectonics: EOS, Transactions, American
Geophysical Union, v. 76, no. 17, p. S-97.
New Jersey Oligocene Sequences Recorded
at the Leg 150X Boreholes (Cape May, Atlantic City, and Island
Beach): Integrated Cenozoic Magneto-, Bio, Chemo- Chronology
and Sequence Stratigraphy: Applications to Global Correlations
and Sea Level, Annual Review Meeting, Woods Hole Oceanographic
Institute, May, 1995.
Pekar, S. F and Miller, K. G., 1994,
Correlation of Oligocene sequences between the New Jersey
and Alabama Coastal Plain: Geological Society of America Abstracts
with Programs, v. 26, p. A-90.
Correlated NJ Oligocene sequences to
the oxygen isotope records and the Haq et al. eustatic record
(1987)
• Oligocene sequences and one
earliest Miocene sequence identified in New Jersey were correlated
to the oxygen isotope proxy of glacioeustasy and the eustatic
record of Haq et al. (1987).
Seven global oxygen isotope increases were recognized by correlating
oxygen isotope records among deep-sea sites; four of these
increases (Oi1, Oi2, Oi2b, and Mi1; 33.5, 30.3, 27.1, and
23.8, respectively) were previously recognized while three
(Oi1a, Oi1b, and Oi2a; 32.8, 31.7, 28.3 Ma, respectively)
were identified in this study. These oxygen isotope increases
correlate well with Oligocene unconformities, indicating a
glacioeustatic control on sequence boundaries.
Publication:
Pekar S. F. and Miller, K. G., 1996,
New Jersey Oligocene "Icehouse" sequences (ODP 150X)
correlated with global d18O and Exxon eustatic records: Geology,
v. 24, p. 567-570.
Abstract:
Pekar, S. F., and Miller, K. G.,
1995, New Jersey Oligocene sequences: eustatics and tectonics:
EOS, Transactions, American Geophysical Union, v. 76, p. S-97.
Early to middle Miocene sequences in
New Jersey were identified
• Early to middle Miocene sequences
and their systems tracts were identified on the New Jersey
coastal plain and were correlated to the deep-sea oxygen isotope
records.
This was accomplished by integrating Sr-isotope chemostratigraphy,
lithofacies, log, and benthic foraminiferal biofacies data.
Correlation of onshore sequence boundaries to oxygen isotope
increases indicate that eustasy was the primary control on
the development of these sequences. Variation along strike
suggests that local tectonics and sediment supply also influence
the preservation of sediments and the stratal architecture
of the New Jersey Miocene sequences.
Publication:
Miller, K. G., Rufolo, S., Gwynn,
D., and Pekar, S. F., 1997, Miocene benthic foraminiferal
biofacies and sequences: in Mountain, G. S., et al., Proceedings
Ocean Drilling Program, Scientific Results, 150X: College,
Texas (Ocean Drilling Program), p. 169-186.
Abstract:
Pekar, S. F., and Miller, K. G.,
Rufolo, S., and Gwynn, D., 1996, New Jersey Oligocene and
Miocene benthic foraminiferal biofacies: systems tracts and
paleobathymetry: Geological Society of America Abstracts with
Programs, v. 28, p. A-117.
Correlated the NJ Oligocene sequences
to other records
• Miocene and Oligocene sequences
identified in New Jersey and in Florida were compared and
were correlated to deep-sea oxygen isotope records records
and inferred eustatic record of Exxon.
The age of the sequence boundaries at both sites showed an
excellent correlation with oxygen isotope records increases
(inferred glacioeustatic lowerings), indicating that global
sea-level change is a primary control in the timing of Oligocene
sequence boundaries for the coastal plain sections studied
here.
Publication:
Sugarman, P. J., McCartan, L., Miller,
K. G., Pekar, S. F., Feigenson, M. D., Kistler, R. W., and
Robinson, A. G., 1997, Strontium-isotopic comparisons of Oligocene
to Miocene sequences, New Jersey and Florida: in Miller, K.
G. and Snyder, S. W., Proceedings Ocean Drilling Program,
Scientific Results, 150X: College, Texas (Ocean Drilling Program),
p. 147-160.
Identified two new Oligocene formations
• Two new Oligocene formations
were formally identified in New Jersey (Sewell Point and the
Atlantic City Formations).
These formations were stratotypified at the Ocean Drilling
Program (ODP) Leg 150X Atlantic City and Cape May boreholes.
The lower to upper Oligocene Sewell Point Formation consists
of glauconitic clays, silts, and clayey glauconite sand. The
upper Oligocene Atlantic City Formation consists of medium-
to coarse-grained glauconitic quartz sands and subordinate
glauconitic clays and silts that overlie the Sewell Point
Formation.
Publication:
Pekar, S. F., Miller, K. G., and Olsson
R. K., 1997, Data report: the Oligocene Sewell Point and Atlantic
City Formations, New Jersey Coastal Plain: in Miller, K. G.
and Snyder, S. W., Proc. Ocean Drilling Program, Scientific
Results, 150X: College, Texas (Ocean Drilling Program), p. 81-90.
Developed a method to estimate eustatic
change and implemented it for the Oligocene
A new method was developed to determine
global sea-level changes for the Oligocene from strata deposited
in New Jersey.
September, 1996 - December, 2001
Lamont-Doherty Earth Observatory of Columbia University and
Rutgers University
This methodology used an innovative approach that combined:
two-dimensional backstripping to reconstruct the stratal geometry,
an integrated chronostratigraphy and lithostratigraphy to
develop a high-resolution sequence stratigraphic framework,
and two-dimensional paleoslope modeling of the benthic foraminiferal
biofacies to estimate water depths. A result of this effort
was the development of a eustatic curve from 34.2 to 23.6
Ma.
Results and publications from this research
Reconstructed the stratal geometry of
Oligocene strata in New Jersey
• The geometry of Oligocene strata in New Jersey was
reconstructed using two-dimensional backstripping results.
This showed that the geometry of these strata were dominated
by the presence of clinoforms since at least the late Eocene,
indicating the timing for the switch from a ramp to clinoformal
geometry on the New Jersey margin. This coincided with global
cooling that occurred during the late Eocene.
Publication:
Pekar, S. F., Miller, K. G., and
Kominz, M. A., 2000, Reconstructing the stratal geometry of
New Jersey Oligocene sequences: resolving a patchwork distribution
into a clear pattern of progradation: Sedimentary Geology,
v. 134, p. 93-109.
Abstracts and Talks:
Correlating the Oxygen Isotope Records
with the New Jersey Oligocene Sequences Recorded at the Leg
150X Boreholes (Cape May, Atlantic City, and Island Beach):
Integrated Cenozoic Magneto, -Bio-, Chemo- Chronology and
Sequence Stratigraphy: Applications to Global Correlations
and Sea Level, Annual Review Meeting, Woods Hole Oceanographic
Institute, May, 1997.
Business Unit Seminar, Chevron Overseas
Petroleum Inc., San Ramon, California, December 1998.
Reconstructing the Stratal Geometry
of New Jersey Oligocene Strata and Estimating Eustasy
Water depths were determined for continental
margin in New Jersey for Oligocene strata
• A new method was developed
to estimate water depths of benthic foraminiferal biofacies
and paleoshelf margins using two-dimensional paleoslope modeling.
This permitted evaluation of water depths at various positions
along the margins and during different times during a sea-level
cycle.
Publication:
Pekar, S. F. and Kominz, M. A., 2001,
Two-dimensional paleoslope modeling: a new method for estimating
water depths for benthic foraminiferal biofacies and paleoshelf
margins: Journal of Sedimentary Research, v. 71, p. 608-620.
Abstract:
Pekar, S. F., and Kominz, M. A.,
2000, Two-dimensional paleoslope modeling: a new method for
estimating water depths for benthic foraminiferal biofacies,
paleoshelf margins, and systems tracts: AAPG Annual Convention,
New Orleans, LA.
Estimated global sea-level changes between
34 and 23 Ma
• A eustatic curve was developed
for the period between 34.2 to 23.6 Ma.
Eustatic amplitudes ranged from 10 to 50 m with the greatest
eustatic change occurring at the base of the Oligocene.
Publication:
Kominz, M. A., and Pekar, S. F.,
2001, Oligocene eustasy from two-dimensional sequence stratigraphic
backstripping: Geological Society of America Bulletin, v.
113, p. 291-304.
Abstracts and Talks:
Constructing a Global Sea-Level Curve
for the Oligocene Using a New Method for Extracting Eustasy
from Onshore New Jersey Sequence Stratigraphy: Woods Hole
Oceanographic Institute, Geology and Geophysics Department
Seminar, November 1999.
Sea-Level Changes During the Middle to Late Eocene and Constructing
a Global Sea-Level Curve From Onshore New Jersey Sequence
Stratigraphy for the Late Paleogene (34.2-23.3 Ma): Penrose
Conference; The Eocene/Oligocene Transition, Evergreen University,
Olympia, WA, August, 1999.
Developing a Eustatic Record From
Western Equatorial Pacific Oxygen Isotope Records and Onshore
New Jersey Oligocene Sequence Stratigraphy: Queens College,
Flushing, NY, May 1999.
Pekar, S. F., and Kominz, M. A.
1999, Extracting a eustatic record from western equatorial
Pacific d18O records and onshore New Jersey Oligocene sequence
stratigraphy, AAPG Annual Convention, San Antonio, TX, 8:A106-A107.
Pekar, S. F., Miller, K. G., Kominz, M., and Wright, J., 1999,
Constructing a eustatic record from onshore New Jersey Oligocene
sequence stratigraphy and western equatorial Pacific oxygen
isotope records (Site 803D): European Union of Geosciences,
Strasbourg, Fr., 4:743.
Constructing a Global Sea-Level Curve From Onshore New Jersey
Sequence Stratigraphy and Western Equatorial Pacific Oxygen
Isotopic Records for the Late Paleogene (34.2-23.6 Ma): Marine
Geology and Geophysics (MG&G) Seminar Series, Lamont-Doherty
Earth Observatory of Columbia University, Palisades, NY, February,
1999.
Evaluated the stratigraphic response on passive margins to
global sea-level changes
• Oligocene eustatic amplitudes
and timings were compared with observed stratigraphic architecture
on the New Jersey continental margin to evaluate stratigraphic
and lithologic response to eustatic change.
The sequence boundaries for which the best age control is
available (<0.3 m.y.), those of late Oligocene age, developed
close to eustatic lows, a phase lag of about one quarter of
a cycle compared with times of most rapid eustatic fall (inflection
points). Condensed sections are similarly offset from times
of most rapid eustatic rise, to near eustatic highs.
Publication:
Pekar, S.F., Christie-Blick, N.,
Kominz, M. A., and Miller, K. G., 2001, Evaluating the stratigraphic
response to eustasy from Oligocene strata in New Jersey: Geology,
v. 29, p. 55-58.
Abstract:
Pekar, S.F., Christie-Blick, N.,
Kominz, M. A., and Miller, K. G., 2000, Establishing the stratigraphic
response to eustasy from Oligocene strata in New Jersey: EOS,
Transactions, American Geophysical Union, v. 81, p. F-667.
Global sea-level changes were calibrated to oxygen isotope
records
Correlation and calibration of global
sea-level amplitudes to oxygen isotope records was accomplished
for the first time for the Oligocene using recently published
eustatic estimates. Each of the nine Oligocene oxygen isotope
events identified in previous studies were correlated to a eustatic
fall. Sea-level amplitudes were calibrated to shallow-dwelling
planktonic foraminiferal oxygen isotope records from Sites 803
(western equatorial Pacific) and 929 (western equatorial Atlantic)
resulting in a maximum value of 0.10 to 0.12‰ for 10 meters
of sea level change, respectively.
Publication:
Pekar, S.F., Christie-Blick, N.,
Kominz, M. A., and Miller, K. G., 2001, Calibrating eustasy
to oxygen isotopes for the early icehouse world of the Oligocene:
Geology, v. 30, p. 903-906.
Abstracts:
Pekar, S.F., Christie-Blick, N.,
Mountain, G.S., 2001, Quantitative constraints on the factors
that control stratigraphic architecture at passive continental
margins: Oligocene sedimentation in New Jersey: Geological
Society of America Annual Meeting, v. 33, no. 6, , p. A-453.
Pekar, S. F., Christie-Blick, N., Miller, K. G., and Kominz,
M. A., Calibrating Oligocene eustasy to oxygen isotope data:
eustatic estimates from two-dimensional flexural backstripping
from the New Jersey continental margin (USA): European Union
of Geosciences Meeting, in Geophysical Research Abstracts,
v. 5, 13,654.
Invited talks:
Using a new method to estimate global
sea-level changes: results and implications from 2-D flexural
backstripping of Oligocene (34-23 Ma) strata: University of
Chicago, Chicago IL, May, 2003
Evaluating Sea-level and Climate
Change from the Greenhouse to Icehouse Worlds: University
of California at Riverside, December, 2002.
The factors that control sedimentation,
accommodation, and stratigraphic architecture on passive continental
margins were evaluated in Oligocene strata in New Jersey.
The following were important in the development of architecture
in the example in this study: 1) progradation of siliciclastic
sediments across the inner part of an existing starved carbonate-dominated
shelf; 2) generally low siliciclastic flux, with in situ production
of authigenic glauconite, especially during times of transgression;
3) a location landward of the hinge zone of the passive margin,
with slow tectonic subsidence augmented by compaction and
sediment loading; 4) low to moderate amplitudes and rates
of eustatic change (10-50 m over spans of ~1-2 m.y.); and
5) an active wave climate that permitted efficient lateral
transport and bypass of sediment at paleodepths as great as
25±10 m.
Publication:
Pekar, S.F., Christie-Blick, N.,
Miller, K. G., and Kominz, M. A., 2003, Evaluating factors
controlling stratigraphic architecture at passive continental
margins: Oligocene sedimentation in New Jersey: Journal of
Sedimentary Research, v. 73, p. 227-245.
Abstract:
Pekar, S.F., Christie-Blick, N.,
Kominz, M. A., and Miller, K. G., 2000, Establishing the stratigraphic
response to eustasy from Oligocene strata in New Jersey: EOS,
Transactions, American Geophysical Union, v. 81. p. F-667.
Developed a new high-resolution chrono-stratigraphic
tool to date Albian strata in West Africa: Sr-chemostratigraphy
Strontium isotope chemostratigraphy
was used as a high-resolution chrono-stratigraphic tool for
the Pinda Formation, nearshore Cabinda, Africa (Albian age).
May, 1996 - September, 1996
Chevron Overseas Petroleum Inc., San Ramon, CA
I was part of a team developing a high-resolution chronostratigraphic
framework for the Pinda Formation (Albian) using Sr-isotope
chemostratigraphy. This was accomplished by integrating lithofacies
analysis, chemostratigraphy (strontium, carbon, and oxygen
isotopes), and water-rock interaction modeling.
Results and publications from
this research.
Water-rock interaction models were
constructed enabling determination of the original Sr-isotope
ratios. This demonstrated that Sr-isotope chemostratigraphy
can be a useful chronostratigraphic tool for West African
Albian carbonate rocks.
Abstract:
Pekar, S. F., Fouke, B., and Dignes,
T, 1998, Strontium isotopic chemostratigraphy of the Pinda
Formation (Albian) offshore Cabinda, Angola: South Atlantic
Mesozoic Correlations, Abstracts of the third Annual Conference,
p. 24-25.
Identified and dated Miocene sequences in offshore West Africa
using an integrated approach
Sequences and systems tracts were identified
and dated from offshore Cabinda (Angola) Miocene strata using
planktonic foraminiferal bio-zones, benthic foraminiferal
biofacies, and lithofacies.
June, 1997-August 1997
Chevron Overseas Petroleum Inc., San Ramon, CA
I performed benthic foraminiferal biofacies analysis, biostratigraphy,
and lithofacies analysis for 60+ samples from upper Miocene
slope cuttings and sidewall cores.
The results were presented in a written
report and an oral presentation to the business unit for Chevron
Overseas Petroleum Inc.
An integrated sequence/seismic stratigraphic
framework was developed for the West African Tertiary, using
benthic foraminiferal biofacies and Sr-isotopic chemostratigraphy
January, 1997 - May 1999
Chevron Overseas Petroleum Inc., San Ramon, CA
I performed benthic foraminiferal biofacies analysis, biostratigraphy,
and lithofacies analysis for 280+ samples from upper Miocene
slope cuttings and sidewall cores. Strontium isotope chemostratigraphy
was performed on multiple samples.
The results were presented in a written report and an oral
presentation to the business unit for Chevron Overseas Petroleum
Inc.
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