Identification of Milankovitch Signals in Middle Triassic Platform carbonate cycles using a super-resolution spectral technique
The Middle Triassic Latemar carbonate buildup of the Dolomites (northern Italy) contains 500 meter-scale cycles (average 0.65 m/cycle) each composed of subtidal deposits overlain by a thin vadose diagenetic cap. The cycles record depositional and early diagenetic responses to glacio-eustatic sea level oscillations with superimposed -- 20,000 year and -- 100,000 year periodicities. Previously, documentation of these Milankovitch periodicities was limited to autocorrelation analyses of truncated sequences (i.e. less than or equal to 45 consecutive cycles) of cycle thicknesses and modeling sedimentation dynamics. To improve the resolution and statistical measure of nonrandom variability in cycle thicknesses, the authors approach Latemar cyclicity using a spectral technique that produces super-resolution spectra of discrete time series. The technique differs from other spectrum estimation procedures in that the time series is ''multitapered'' as a consequence of expanding its Fourier transform by an ordered set of spheroidal functions. The resulting high-resolution spectrum estimates have a greatly enhanced statistical stability that permits the detection of extremely narrow-band signals in noisy data sets that are likely to be missed by traditional spectral analysis. The application of this multitapering algorithm on 140 consecutive Latemar cycles reveals nine statistically significant harmonies controlling cycle development, all with periodicities corresponding to those of Berger's modeled series for the Earth's orbital eccentricity and axial tilt. The authors believe this to be the first report of evidence for multiple, superimposed high-resolution Milankovitch spectra in the pre-Pleisocene shallow marine, platform carbonate record.
- OSTI ID:
- 6591669
- Report Number(s):
- CONF-880301-
- Resource Relation:
- Conference: Annual meeting of the American Association of Petroleum Geologists, Houston, TX, USA, 20 Mar 1988
- Country of Publication:
- United States
- Language:
- English
Similar Records
Platform/foreslope facies and buildup geometry resulting from short-term and long-term eustatic sea level fluctuations: latemar buildup (Middle Triassic), Dolomites, northern Italy
Forward modeling of high-frequency, glacio-eustatic, depositional sequences: An example from Middle Pennsylvanian shelf carbonates of the SW Paradox basin, Honaker Trail, Utah
Related Subjects
03 NATURAL GAS
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
CARBONATE ROCKS
SEDIMENTATION
DOLOMITE
NATURAL GAS DEPOSITS
COMPUTERIZED SIMULATION
PETROLEUM DEPOSITS
SOURCE ROCKS
ALGORITHMS
CATAGENESIS
DEPOSITION
EXPLORATION
GEOLOGIC MODELS
PETROLEUM GEOLOGY
PLEISTOCENE EPOCH
SPECTRA
TRIASSIC PERIOD
ALKALINE EARTH METAL COMPOUNDS
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CARBON COMPOUNDS
CARBONATE MINERALS
CARBONATES
CENOZOIC ERA
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGY
MAGNESIUM CARBONATES
MAGNESIUM COMPOUNDS
MATHEMATICAL LOGIC
MESOZOIC ERA
MINERAL RESOURCES
MINERALS
OXYGEN COMPOUNDS
QUATERNARY PERIOD
RESOURCES
ROCKS
SEDIMENTARY ROCKS
SIMULATION
020200* - Petroleum- Reserves
Geology
& Exploration
030200 - Natural Gas- Reserves
Geology
& Exploration
990220 - Computers
Computerized Models
& Computer Programs- (1987-1989)