Sea level fluctuation is caused by several factors. The major factors affecting sea level are the shape and volume of the basin of deposition, volume of the water contained therein, and tectonic uplift and subsidence. Depending upon their magnitude, their duration and affected area also varies. Some of them are of global influence whereas others are regional or localized. Sea level fluctuations greatly affect sedimentation process in the basin. This is ultimately reflected in the stratigraphic setting of the region.
Dear Dr. Saxena:
You gave already a summary of the reasons behind sea level fluctuations. There are two simple states. An increase of the sea level gives rise to an encroachment of marine strata upon land, increasing in thickness vertically upward in the stratigraphic column and laterally causing the marine facies to move further inland. A lowering of the sea level causes a reverse trend and signaled also in the stratigraphic column.
H.G.Dill
Dear colleague Saxena,
Your question immediately refers to the one best publication, called by many geologists as "the bible": the AAPG Memoir 26.
I strongly suggest that you read chapter 1 – 6 (Mitchum, Vail and Sangree: “Seismic stratigraphy and global changes of sea level”, in C.E.Payton, ed., Seismic Stratigraphy – Applications to Hydrocarbon Exploration: AAPG Memoir 26, p. 117-143. Also, I recommend reading the SEPM Special Publication 42.
Of course, with the passage of time, geophysical techniques have been modified, especially in relation to
1_ the extraction of seismic attributes, which allow you to go more easily to the fundamental concepts expressed there.
2_ the massive use of the 3D-seismic data, not only 2-D seismic such as explain that foundational and landmark publication.
Although some paradigms and schools of thought have departed from Memoir 26, I consider it as a geologist is a fundamental milestone for the understanding of the phenomena of the relative changes of the base level - sea level - which are referred to in your question. Another very good material is published by Cross and Lessenger (Ann. Rev. Earth and Planetary Science, 1988, 16: 319-354 Seismic Stratigraphy.
I attach a material for your review, I hope you find it useful.
Mario E. sigismondi
There is no better reference than Catuneanu, C (2019), Earth Science Reviews 188, 312-388 which builds on Posamentier and other global authorities. All variables contributing to sedimentary cycles are fully explained.
Stratigraphic style and sedimentary pattern of any basin filled with marine sediments depend on the sea-level fluctuation, transgressive/regressive processes. There are several literature available on this.
You also need to consider what types of sediments you are dealing with. For example carbonates may respond to sea-level changes differently than siliciclastics. Here's a reference to a book that includes a brief discussion of carbonates in addition to siliciclastics. The Sedimentary Record of Sea-Level Change, 2003, Angela Coe (ed), Cambridge University Press, 287 p.
Dear Trev,
It is almost impossible to cite all authors without making any important omissions. You are right to name Octavian Catuneanu for example. Even Octavian Catuneanu is currently making important contributions with other colleagues in understanding the sequential stratigraphy of the Neuquina basin, Argentina, where I live. I attach a recent material by this author, published this year, regarding the importance of driven scales in sequential stratigraphy, at Marine and Petroleum Geology 106 (2019) 128-159. "...Scale is a key issue in sequence stratigraphy, with implications for methodology, nomenclature, and practical applications..." wrote the author.
Best regards,
Mario E. Sigismondi
Completely agree; three classic works by Octavian et al. : Marine and Petroleum Geology 106 (2019) 128-159, Earth-Science Reviews 188 (2019) 313-388, and Earth-Science Reviews 92:1-2 (2009) 1-33. Essential, current reading for all stratigraphers of any age! Excellent examples from the Neuquina Basin; with similar potential in the Flinders Ranges of South Australia where I work. Thanks for your input here.
A simple logic: sea level fluctuations directly correspond to creation (SL Rise) or destruction (SL fall) of accommodation space in the receiving basins. The changes in accommodation space results in preservation or erosion of sediments deposited. Now, you have the direct answer to your question: how sea level fluctuations influence stratigraphy?
To be clear, all these questions are covered by Octavian Catuneanu, and his co-authors, in the landmark papers: Marine and Petroleum Geology 106 (2019) 128-159, Earth-Science Reviews 188 (2019) 313-388, and Earth-Science Reviews 92:1-2 (2009) 1-33. These works are essential reading for any stratigrapher.
The entire gamut of Stratigraphy, including the Lithostratigraphy, Biostratigraphy and Sequence Stratigraphy are a play of sea level fluctuations in any sedimentary basin.
At low rates of sea-level fall and/or high rates of sediment supply deposition occurs as the shoreline moves seawards. If the rate of sea-level fall is relatively high and the rate of sedimentation is low, there is no sedimentation, and there may be erosion.
Aspects of the rock such as the rock type, the position of sedimentary structures, and sequencing of the rocks tell geologists about overall changes in the environment in an area (Heinz and Aigner, 2003). Geologists can also look at sea level changes on a global scale.
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