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The AAPG/Datapages Combined Publications Database

AAPG Bulletin


Volume: 47 (1963)

Issue: 2. (February)

First Page: 374

Last Page: 374

Title: Use of the Vertical Profile in Environmental Reconstruction: ABSTRACT

Author(s): Glenn S. Visher

Article Type: Meeting abstract


The relation of the vertical stratigraphic succession to areal depositional patterns was first observed by Johannes Walther and is known as Walther's Law of Facies. Each depositional unit in a vertical stratigraphic succession is the result of a particular sedimentary environment. When these units are compiled vertically, they represent a sequence of environments characteristic of a specific over-all sedimentary process such as regression or transgression. These environmental successions are definite and recognizable and may be used to define over-all sedimentary processes in ancient rocks. Therefore, environmental sequences provide a reference framework for interpreting the sedimentary history of any stratigraphic section.

Only a limited number of specific vertical sequences has been found in a comparative study of Recent and ancient sediments. The following sequences have been developed into models of sedimentation.

Regressive Marine

c. Marine shale or lagoonal deposits
b. Thin-bedded sand/silt and shale
a. Poorly bedded shale
Lowermost units are deposited below wave base; higher units close to sea-level.

Fluvial (channel or valley-fill sequence)

d. Ripple cross-laminated zone
c. Laminated, even-bedded sand/silt zone
b. Festoon cross-bedded zone
a. Basal conglomeratic bedload zone

Deltaic Sequences

Regressive marine sequences overlain by nearshore fluvial, bay, and marsh deposits; characterized by extensive marine deposits and variable non-marine sediment distribution patterns.

Transgressive Marine

b. Marine shales or fragmental limestones
a. Sand or silt
Widespread distribution and thinness are diagnostic; basal unit abruptly overlies shale in many instances; gradation upward into marine shale is rapid.

Bathyal-Abyssal Sediments

Widely distributed, thin-bedded; fauna and sedimentary structures characteristic of deeper water.

Lacustrine Sediments

Resembles regressive marine sequences, but is developed on a smaller scale and lacks marine fauna.

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Copyright 1997 American Association of Petroleum Geologists