PRELIMINARY SEQUENCE AND EVENT PRELIMINARY SEQUENCE AND EVENT STRATIGRAPHIC CORRELATIONS STRATIGRAPHIC CORRELATIONS
WITHIN THE HELDERBERG GROUP WITHIN THE HELDERBERG GROUP (SILURIAN-DEVONIAN) BETWEEN(SILURIAN-DEVONIAN) BETWEEN
NEW YORK AND THE CENTRAL NEW YORK AND THE CENTRAL APPALACHIAN BASINAPPALACHIAN BASIN
James R. EbertJames R. Ebert
Damon K. MattesonDamon K. Matteson
SUNY College at OneontaSUNY College at Oneonta
New York: Appalachian Standard SuccessionNew York: Appalachian Standard Succession
Late nineteenth and Late nineteenth and early twentieth century early twentieth century studiesstudiesJohnson and Murphy Johnson and Murphy (1969)(1969)Helderberg GroupHelderberg GroupSilurian-DevonianSilurian-Devonian– PPřídolí-Lochkovianřídolí-Lochkovian– Predominantly limestonePredominantly limestone– Some shaly unitsSome shaly units
Primacy of New YorkPrimacy of New Yorkin the Early Literaturein the Early Literature
Early Twentieth Century Stratigraphy and Early Twentieth Century Stratigraphy and Correlations to New York based on:Correlations to New York based on:– General lithologic similaritiesGeneral lithologic similarities– Faunal similaritiesFaunal similarities
Names from New York applied from New Names from New York applied from New Jersey to Virginia – the Central Jersey to Virginia – the Central Appalachian Basin (CAB)Appalachian Basin (CAB)
A New View of Helderberg StratigraphyA New View of Helderberg Stratigraphy
Rickard (1962) - migrating coeval faciesRickard (1962) - migrating coeval facies
Laporte (1969) – spectrum of ramp environmentsLaporte (1969) – spectrum of ramp environments
Rickard’s (1962) migrating coeval facies Rickard’s (1962) migrating coeval facies influences correlationsinfluences correlations– in the CABin the CAB– between NY and the CABbetween NY and the CAB
Head (1969, 1972, 1974)Head (1969, 1972, 1974)
Dorobek (1984), Dorobek and Read (1986)Dorobek (1984), Dorobek and Read (1986)
Rickard’s Stratigraphy and the Role of Rickard’s Stratigraphy and the Role of the Appalachian Standard Successionthe Appalachian Standard Succession
Revised Helderberg Stratigraphy – New YorkRevised Helderberg Stratigraphy – New YorkEbert and Matteson (2003a,b)Ebert and Matteson (2003a,b)
Rationale for Revised StratigraphyRationale for Revised Stratigraphy
Contacts are Contacts are unconformableunconformable
Clarifies placement of the Clarifies placement of the S/D boundary based on S/D boundary based on conodontsconodonts
New Questions in a Classic SettingNew Questions in a Classic Setting
How does the presence of unconformities in NY affect correlations within the CAB and between NY and the CAB?
Are these unconformities widespread? Can they be recognized in the CAB and used as a framework for correlation?
What are the relative roles of eustatic and What are the relative roles of eustatic and tectonic processes in producing the tectonic processes in producing the unconformities?unconformities?
Can basin-wide revision of Helderberg Can basin-wide revision of Helderberg stratigraphy provide new insights on global sea stratigraphy provide new insights on global sea level change around the S/D boundary?level change around the S/D boundary?
Framework for Stratigraphic CorrelationsFramework for Stratigraphic Correlations
Working model of early correlationsWorking model of early correlations
Examination of contactsExamination of contacts– Evidence of erosionEvidence of erosion– Evidence of sediment starvationEvidence of sediment starvation
Biostratigraphic data – FAD Biostratigraphic data – FAD Icriodus woschmidtiIcriodus woschmidti
Unique faunal occurrences - Unique faunal occurrences - ScyphocrinitesScyphocrinites
Recognition of events and marker bedsRecognition of events and marker beds– Distinctive facies/lithologies - twoDistinctive facies/lithologies - two– Episodes of siliciclastic influxEpisodes of siliciclastic influx– Trangressive maxima - twoTrangressive maxima - two– Bald Hill K-bentonitesBald Hill K-bentonites
New York CAB New Scotland Upper Mandata
Upper Kalkberg Bald Hill K-bentonites
Mandata Shale Bald Hill K-bentonites
? Phosphate & pyrite nodules Bald Hill K-bentonites
Kalkberg Bald Hill K-bentonites Corriganville Limestone
Punch Kill Unconformity/Black Shale Coeymans (Ravena/Deansboro) New Creek Limestone L
och
kovi
an
Howe Cave Unconformity First Icriodus woschmidti – Silurian/Devonian Boundary
Elmwood/CR/Jamesville Upper Keyser Olney/Dayville Jersey Shore Member
Terrace Mountain Unconformity/Glauconitic limestone
Green Vedder Member Scyphocrinites
Big Mountain Shale Scyphocrinites
Clockville Discontinuity/Pyritic hardground Thacher Member Byers Island Member
Minelot Falls/Tonoloway-Keyser Unconformity Rondout – Chrysler Mbr. Tonoloway
Pří
do
lí
Cobleskill Skeletal zone in Tonoloway ?
Sequence 1: Manlius/Lower KeyserSequence 1: Manlius/Lower Keyser
New York CAB
New Scotland Upper Mandata Upper Kalkberg
Bald Hill K-bentonites Mandata Shale
Bald Hill K-bentonites ? Phosphate & pyrite nodules
Bald Hill K-bentonites Kalkberg
Bald Hill K-bentonites Corriganville Limestone
Punch Kill Unconformity/Black Shale Coeymans (Ravena/Deansboro) New Creek Limestone
First Icriodus woschmidti – S/D Boundary Howe Cave Unconformity
Elmwood/CR/Jamesville Upper Keyser Olney/Dayville Jersey Shore Member
Terrace Mountain Unconformity/Glauconitic limestone
Green Vedder Member Scyphocrinites
Big Mountain Shale Scyphocrinites
Clockville Discontinuity/Pyritic hardground Thacher Member Byers Island Member
Minelot Falls/Tonoloway-Keyser Unconformity Rondout – Chrysler Mbr. Tonoloway
Cobleskill Skeletal zone in Tonoloway ?
Sequence 2:Sequence 2:Green Vedder/Big Mountain ShaleGreen Vedder/Big Mountain Shale
New York CAB
New Scotland Upper Mandata Upper Kalkberg
Bald Hill K-bentonites Mandata Shale
Bald Hill K-bentonites ? Phosphate & pyrite nodules
Bald Hill K-bentonites Kalkberg
Bald Hill K-bentonites Corriganville Limestone
Punch Kill Unconformity/Black Shale Coeymans (Ravena/Deansboro) New Creek Limestone
First Icriodus woschmidti – S/D Boundary Howe Cave Unconformity
Elmwood/CR/Jamesville Upper Keyser Olney/Dayville Jersey Shore Member
Terrace Mountain Unconformity/Glauconitic limestone
Green Vedder Member Scyphocrinites
Big Mountain Shale Scyphocrinites
Clockville Discontinuity/Pyritic hardground Thacher Member Byers Island Member Minelot Falls/Tonoloway-Keyser Unconformity
Rondout – Chrysler Mbr. Tonoloway Cobleskill Skeletal zone in Tonoloway ?
First Transgressive Maximum and First Transgressive Maximum and Siliciclastic-bearing UnitsSiliciclastic-bearing Units
New York CAB
New Scotland Upper Mandata Upper Kalkberg
Bald Hill K-bentonites Mandata Shale
Bald Hill K-bentonites ? Phosphate & pyrite nodules
Bald Hill K-bentonites Kalkberg
Bald Hill K-bentonites Corriganville Limestone
Punch Kill Unconformity/Black Shale Coeymans (Ravena/Deansboro) New Creek Limestone
First Icriodus woschmidti – S/D Boundary Howe Cave Unconformity
Elmwood/CR/Jamesville Upper Keyser Olney/Dayville Jersey Shore Member
Terrace Mountain Unconformity/Glauconitic limestone
Green Vedder Member Scyphocrinites
Big Mountain Shale Scyphocrinites
Clockville Discontinuity/Pyritic hardground Thacher Member Byers Island Member Minelot Falls/Tonoloway-Keyser Unconformity
Rondout – Chrysler Mbr. Tonoloway Cobleskill Skeletal zone in Tonoloway ?
Sequence 3: Dayville/U. Manlius/U. KeyserSequence 3: Dayville/U. Manlius/U. Keyser
New York CAB
New Scotland Upper Mandata Upper Kalkberg
Bald Hill K-bentonites Mandata Shale
Bald Hill K-bentonites ? Phosphate & pyrite nodules
Bald Hill K-bentonites Kalkberg
Bald Hill K-bentonites Corriganville Limestone
Punch Kill Unconformity/Black Shale Coeymans (Ravena/Deansboro) New Creek Limestone
First Icriodus woschmidti – S/D Boundary Howe Cave Unconformity
Elmwood/CR/Jamesville Upper Keyser Olney/Dayville Jersey Shore Member
Terrace Mountain Unconformity/Glauconitic limestone
Green Vedder Member Scyphocrinites
Big Mountain Shale Scyphocrinites
Clockville Discontinuity/Pyritic hardground Thacher Member Byers Island Member Minelot Falls/Tonoloway-Keyser Unconformity
Rondout – Chrysler Mbr. Tonoloway Cobleskill Skeletal zone in Tonoloway ?
Sequence 4: Coeymans/New CreekSequence 4: Coeymans/New Creek
First Icriodus woschmidti - Silurian/Devonian BoundaryHCU is erosional throughout the basin
New York CAB
New Scotland Upper Mandata Upper Kalkberg
Bald Hill K-bentonites Mandata Shale
Bald Hill K-bentonites ? Phosphate & pyrite nodules
Bald Hill K-bentonites Kalkberg
Bald Hill K-bentonites Corriganville Limestone
Punch Kill Unconformity/Black Shale Coeymans (Ravena/Deansboro) New Creek Limestone
First Icriodus woschmidti – S/D Boundary Howe Cave Unconformity
Elmwood/CR/Jamesville Upper Keyser Olney/Dayville Jersey Shore Member
Terrace Mountain Unconformity/Glauconitic limestone
Green Vedder Member Scyphocrinites
Big Mountain Shale Scyphocrinites
Clockville Discontinuity/Pyritic hardground Thacher Member Byers Island Member Minelot Falls/Tonoloway-Keyser Unconformity
Rondout – Chrysler Mbr. Tonoloway Cobleskill Skeletal zone in Tonoloway ?
Sequence 5:Kalkberg/Corriganville
New York CAB
New Scotland Upper Mandata Upper Kalkberg
Bald Hill K-bentonites Mandata Shale
Bald Hill K-bentonites ? Phosphate & pyrite nodules
Bald Hill K-bentonites Kalkberg
Bald Hill K-bentonites Corriganville Limestone
Punch Kill Unconformity/Black Shale Coeymans (Ravena/Deansboro) New Creek Limestone
First Icriodus woschmidti – S/D Boundary Howe Cave Unconformity
Elmwood/CR/Jamesville Upper Keyser Olney/Dayville Jersey Shore Member
Terrace Mountain Unconformity/Glauconitic limestone
Green Vedder Member Scyphocrinites
Big Mountain Shale Scyphocrinites
Clockville Discontinuity/Pyritic hardground Thacher Member Byers Island Member Minelot Falls/Tonoloway-Keyser Unconformity
Rondout – Chrysler Mbr. Tonoloway Cobleskill Skeletal zone in Tonoloway ?
?An Undiscovered Unconformity in NY?
New York CAB
New Scotland Upper Mandata Upper Kalkberg
Bald Hill K-bentonites Mandata Shale
Bald Hill K-bentonites ? Phosphate & pyrite nodules
Bald Hill K-bentonites Kalkberg
Bald Hill K-bentonites Corriganville Limestone
Punch Kill Unconformity/Black Shale Coeymans (Ravena/Deansboro) New Creek Limestone
First Icriodus woschmidti – S/D Boundary Howe Cave Unconformity
Elmwood/CR/Jamesville Upper Keyser Olney/Dayville Jersey Shore Member
Terrace Mountain Unconformity/Glauconitic limestone
Green Vedder Member Scyphocrinites
Big Mountain Shale Scyphocrinites
Clockville Discontinuity/Pyritic hardground Thacher Member Byers Island Member Minelot Falls/Tonoloway-Keyser Unconformity
Rondout – Chrysler Mbr. Tonoloway Cobleskill Skeletal zone in Tonoloway ?
Bald Hill K-bentonitesBald Hill K-bentonites
Age of S/D Boundary - 418 MaAge of S/D Boundary - 418 Ma(Tucker, et. al. 1998)(Tucker, et. al. 1998)
Basin-wide markersBasin-wide markers(Smith, Berkheiser and Way 1986)(Smith, Berkheiser and Way 1986)
Second Transgressive MaximumSecond Transgressive Maximum
New York CAB
New Scotland Upper Mandata Upper Kalkberg
Bald Hill K-bentonites Mandata Shale
Bald Hill K-bentonites ? Phosphate & pyrite nodules
Bald Hill K-bentonites Kalkberg
Bald Hill K-bentonites Corriganville Limestone
Punch Kill Unconformity/Black Shale Coeymans (Ravena/Deansboro) New Creek Limestone
First Icriodus woschmidti – S/D Boundary Howe Cave Unconformity
Elmwood/CR/Jamesville Upper Keyser Olney/Dayville Jersey Shore Member
Terrace Mountain Unconformity/Glauconitic limestone
Green Vedder Member Scyphocrinites
Big Mountain Shale Scyphocrinites
Clockville Discontinuity/Pyritic hardground Thacher Member Byers Island Member Minelot Falls/Tonoloway-Keyser Unconformity
Rondout – Chrysler Mbr. Tonoloway Cobleskill Skeletal zone in Tonoloway ?
New York CAB New Scotland Upper Mandata
Upper Kalkberg Bald Hill K-bentonites
Mandata Shale Bald Hill K-bentonites
? Phosphate & pyrite nodules Bald Hill K-bentonites
Kalkberg Bald Hill K-bentonites Corriganville Limestone
Punch Kill Unconformity/Black Shale Coeymans (Ravena/Deansboro) New Creek Limestone L
och
kovi
an
Howe Cave Unconformity First Icriodus woschmidti – Silurian/Devonian Boundary
Elmwood/CR/Jamesville Upper Keyser Olney/Dayville Jersey Shore Member
Terrace Mountain Unconformity/Glauconitic limestone
Green Vedder Member Scyphocrinites
Big Mountain Shale Scyphocrinites
Clockville Discontinuity/Pyritic hardground Thacher Member Byers Island Member
Minelot Falls/Tonoloway-Keyser Unconformity Rondout – Chrysler Mbr. Tonoloway
Pří
do
lí
Cobleskill Skeletal zone in Tonoloway ?
ConclusionsConclusionsNY unconformities can be traced into CABNY unconformities can be traced into CAB
Most unconformities in NY are erosionalMost unconformities in NY are erosional
Most in the CAB are marked by sediment starvationMost in the CAB are marked by sediment starvation
Minelot Falls/Tonoloway-Keyser Unconformity and Minelot Falls/Tonoloway-Keyser Unconformity and Howe Cave Unconformity are erosional throughout Howe Cave Unconformity are erosional throughout basinbasin
A PA Přídolířídolí transgressive maximum is now recognized transgressive maximum is now recognized
Sequence and event stratigraphic correlations Sequence and event stratigraphic correlations between NY and the CAB are similar to those between NY and the CAB are similar to those proposed in the early twentieth centuryproposed in the early twentieth century
Correlations are preliminary; much more work Correlations are preliminary; much more work needs to be done!needs to be done!
New York CAB New Scotland Upper Mandata
Upper Kalkberg Bald Hill K-bentonites
Mandata Shale Bald Hill K-bentonites
? Phosphate & pyrite nodules Bald Hill K-bentonites
Kalkberg Bald Hill K-bentonites Corriganville Limestone
Punch Kill Unconformity/Black Shale Coeymans (Ravena/Deansboro) New Creek Limestone L
och
kovi
an
Howe Cave Unconformity First Icriodus woschmidti – Silurian/Devonian Boundary
Elmwood/CR/Jamesville Upper Keyser Olney/Dayville Jersey Shore Member
Terrace Mountain Unconformity/Glauconitic limestone
Green Vedder Member Scyphocrinites
Big Mountain Shale Scyphocrinites
Clockville Discontinuity/Pyritic hardground Thacher Member Byers Island Member
Minelot Falls/Tonoloway-Keyser Unconformity Rondout – Chrysler Mbr. Tonoloway
Pří
do
lí
Cobleskill Skeletal zone in Tonoloway ?