# stratigraphy

> study of rock layers and the layering process

**Wikidata**: [Q134783](https://www.wikidata.org/wiki/Q134783)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Stratigraphy)  
**Source**: https://4ort.xyz/entity/stratigraphy

## Summary
Stratigraphy is the scientific study of rock layers (strata) and the processes that produce layering. It is a subdiscipline of geology that includes multiple specialized methods for describing, correlating, and interpreting sedimentary and other layered rocks.

## Key Facts
- Wikidata description: "study of rock layers and the layering process."
- Alias: stratigraphic geology.
- Wikipedia title: Stratigraphy.
- Sitelink count (aggregated links to sources): 80.
- Contains the subfield palaeogeography — the study of historical geography (sitelink_count: 57).
- Contains the subfield biostratigraphy — study of relative ages of rock strata using fossils (sitelink_count: 35).
- Contains the subfield sequence stratigraphy — study and analysis of groups of sedimentary deposits (sitelink_count: 10).
- Part of the broader discipline geology — the study of the composition, structure, physical properties, and history of Earth's components and the processes that shape them (sitelink_count: 215).
- Related parent/method fields and specialties include lithostratigraphy (method of establishing stratigraphical units; sitelink_count: 25), chronostratigraphy (study of relative time relations and ages of rock layers; sitelink_count: 27), archaeological stratigraphy (specialty of archaeology and stratigraphy; sitelink_count: 16), magnetostratigraphy (method of dating sedimentary and volcanic rocks; sitelink_count: 15), chemostratigraphy (concept and technique in geology; sitelink_count: 6), and sequence stratigraphy (sitelink_count: 10).
- Biostratigraphy appears in the parent/specialty list as well as a contained subsidiary (study of relative ages of rock strata using fossils; sitelink_count: 35).
- Stratigraphy is categorized as an academic discipline and a field of study (academic discipline sitelink_count: 50; field of study sitelink_count: 12).
- The International Commission on Stratigraphy is a related organization; its inception is listed as 1974 (inception: 1974; sitelink_count: 36).
- No SEO data available for stratigraphy in the provided source material.

Notable people associated with stratigraphy or listed as related (name — descriptor; listed occupations and citizenships as provided; sitelink_count):
- Luis Garicano — Spanish economist (occupations listed; citizenship: Spain; sitelink_count: 11).
- Marie-Henriette Alimen — French archaeologist and prehistorian (1900–1996; occupations listed; citizenship: France; sitelink_count: 5).
- Adolf von Koenen — German geologist and paleontologist (1837–1915; occupations listed; citizenship: Germany, [additional code]; sitelink_count: 8).
- Emanuel Kayser — German scientist (1845–1927; occupations listed; citizenship: Germany; sitelink_count: 8).
- Helen Belyea — Canadian geologist (occupations listed; citizenship: Canada; sitelink_count: 10).
- Julia Anna Gardner — American geologist (1882–1960; occupations listed; citizenship: United States; sitelink_count: 9).
- Ethel Skeat — English stratigrapher, invertebrate paleontologist, and geologist (occupations listed; citizenship: England, [additional code]; sitelink_count: 5).
- Nikolay Shatsky — Soviet geologist (1895–1960; occupations listed; citizenship: USSR-related codes; sitelink_count: 12).
- Wilhelm Salomon-Calvi — German paleontologist (1868–1941; occupations listed; citizenship: Germany; sitelink_count: 6).
- Charles Elmer Resser — American paleontologist (1889–1943; occupations listed; citizenship: United States; sitelink_count: 5).
- Perceval de Loriol — Swiss paleontologist (1828–1908; occupations listed; citizenship: Switzerland; sitelink_count: 7).
- Alexei Petrovich Pavlov — Russian geologist (1854–1929; occupations listed; citizenships listed; sitelink_count: 13).
- Jerzy Dzik — Polish paleontologist (occupations listed; citizenship: Poland; sitelink_count: 6).
- Tove Birkelund — Danish geologist (1928–1986; occupations listed; citizenship: Denmark; sitelink_count: 6).
- Richard Foster Flint — American geologist (1902–1976; occupations listed; citizenship: United States; sitelink_count: 8).
- Preston Cloud — American earth scientist, biogeologist, cosmologist, and paleontologist (1912–1991; occupations listed; citizenship: United States; sitelink_count: 14).
- Augusto Gansser-Biaggi — Swiss geologist (1910–2012; occupations listed; citizenship: Switzerland; sitelink_count: 10).
- Alcide d'Orbigny — French scientist (1802–1857; occupations listed extensively; citizenship: France; sitelink_count: 43).
- Alexander Karpinsky — Russian geologist and president of the Russian Academy of Sciences (1847–1936; occupations listed; citizenships listed; sitelink_count: 26).
- Peter Vail — American geologist (occupations listed; citizenship: United States; sitelink_count: 6).
- Stig Bergström — Swedish paleontologist and geologist (occupations listed; citizenship: Sweden; sitelink_count: 5).
- Wilhelm von Branca — German geologist and paleontologist (1844–1928; occupations listed; citizenship: Germany; sitelink_count: 9).

## FAQs
Q: What exactly does stratigraphy study?
A: Stratigraphy studies rock layers (strata) and the processes that create and arrange those layers, including methods to describe, correlate, and interpret layered rocks.

Q: What are the main subfields within stratigraphy?
A: Major subfields include palaeogeography (historical geography), biostratigraphy (using fossils to determine relative ages), and sequence stratigraphy (analysis of groups of sedimentary deposits). Additional methods related to stratigraphy include lithostratigraphy, chronostratigraphy, magnetostratigraphy, and chemostratigraphy.

Q: Is stratigraphy part of geology or archaeology?
A: Stratigraphy is part of geology and also has an archaeological specialty known as archaeological stratigraphy; it functions across both earth-science and archaeological contexts.

Q: Which organization sets scientific definitions for stratigraphic practice?
A: The International Commission on Stratigraphy is the commission related to stratigraphy; its inception is recorded as 1974 and it is tasked with scientific definitions of geological stratigraphy of the Earth.

Q: Who are some people historically associated with stratigraphy?
A: The provided source lists many figures connected to stratigraphy and related earth sciences, including Alcide d'Orbigny, Peter Vail, Preston Cloud, Alexei P. Pavlov, and others; these individuals are identified with occupations such as geologist, paleontologist, and stratigrapher.

Q: Are there different methods to date or correlate strata?
A: Yes. Methods mentioned in the source include biostratigraphy (fossil-based relative dating), chronostratigraphy (study of relative time relations and ages), magnetostratigraphy (dating using magnetic signatures), chemostratigraphy (chemical signals), and lithostratigraphy (establishing stratigraphical units).

## Why It Matters
Stratigraphy provides the foundational framework for understanding the vertical and lateral arrangement of rock layers, which is essential for reconstructing Earth's history. By organizing strata into units and subunits and applying methods such as biostratigraphy and chronostratigraphy, stratigraphy enables relative dating of rock sequences and the reconstruction of past environments through palaeogeography. Specialized approaches such as sequence stratigraphy analyze groups of sedimentary deposits to interpret depositional processes and basin history. The discipline connects geology and archaeology through archaeological stratigraphy, supporting chronological control for human and environmental records. International bodies like the International Commission on Stratigraphy formalize definitions and standards, making stratigraphic practice consistent and comparable across scientific studies. Because stratigraphy integrates multiple methods (lithostratigraphy, magnetostratigraphy, chemostratigraphy, etc.), it functions as a central organizing science for studies of Earth's layered records and their interpretation.

## Notable For
- Being defined succinctly as the study of rock layers and the layering process.
- Hosting specialized subfields that each address different aspects of layered-rock analysis: palaeogeography, biostratigraphy, and sequence stratigraphy.
- Integrating a variety of stratigraphic methods: lithostratigraphy, chronostratigraphy, magnetostratigraphy, chemostratigraphy, and biostratigraphy.
- Serving both geology and archaeology through archaeological stratigraphy.
- Being linked with a formal international body, the International Commission on Stratigraphy (inception 1974), which is tasked with scientific definitions for geological stratigraphy.
- Association with numerous historical and modern scientists in geology and paleontology (many named figures with documented occupations and nationalities).

## Body

### Overview / Definition
- Stratigraphy is defined as the study of rock layers (strata) and the processes that create layering.
- The term is also presented under the alias "stratigraphic geology."
- The topic is represented on Wikipedia under the title "Stratigraphy" and has an aggregated sitelink_count of 80 in the provided data.

### Subfields and Subsidiaries
- Palaeogeography: Listed as a contained subsidiary. It focuses on the study of historical geography and has a sitelink_count of 57.
- Biostratigraphy: Identified both as a subsidiary that stratigraphy contains and as a related parent method. It specifically studies relative ages of rock strata using fossils and has a sitelink_count of 35.
- Sequence stratigraphy: A contained subsidiary that studies and analyzes groups of sedimentary deposits. The listed sitelink_count is 10.

### Parent Fields, Methods, and Related Specialties
- Geology: Stratigraphy is part of geology, which studies Earth's composition, structure, properties, history, and shaping processes (sitelink_count: 215).
- Lithostratigraphy: A parent-listed method for establishing stratigraphical units (sitelink_count: 25).
- Chronostratigraphy: The study of relative time relations and ages of rock layers; listed as a parent (sitelink_count: 27).
- Archaeological stratigraphy: Identified as a specialty interlinking archaeology and stratigraphy (sitelink_count: 16).
- Magnetostratigraphy: A method of dating sedimentary and volcanic rocks, listed under parent fields (sitelink_count: 15).
- Chemostratigraphy: Identified as a concept and technique in geology related to stratigraphy (sitelink_count: 6).
- Note: Biostratigraphy is repeated in the parent listing as well as in the contained-subsidiaries list, underscoring its dual role as a distinct method and a subdiscipline.

### Organizations
- International Commission on Stratigraphy: Presented as a related entity tasked with scientific definitions of geological stratigraphy of the Earth. Its inception is recorded in the source as 1974 and it has a sitelink_count of 36.

### Academic Context
- Stratigraphy is categorized as an academic discipline and a field of study. The source lists "academic discipline" (sitelink_count: 50) and "field of study" (sitelink_count: 12) as related items, indicating its institutional and pedagogical place within higher education and research.

### Notable People and Contributions
- The source lists numerous individuals connected to stratigraphy or related fields. Each is identified with descriptors and listed occupations/citizenships where provided:
  - Alcide d'Orbigny — French scientist (1802–1857); large sitelink_count: 43.
  - Alexei Petrovich Pavlov — Russian geologist (1854–1929); sitelink_count: 13.
  - Alexander Karpinsky — Russian geologist and president of the Russian Academy of Sciences (1847–1936); sitelink_count: 26.
  - Preston Cloud — American earth scientist, biogeologist, cosmologist, and paleontologist (1912–1991); sitelink_count: 14.
  - Peter Vail — American geologist; sitelink_count: 6.
  - Luis Garicano — Spanish economist; sitelink_count: 11.
  - Marie-Henriette Alimen — French archaeologist and prehistorian (1900–1996); sitelink_count: 5.
  - Adolf von Koenen — German geologist and paleontologist (1837–1915); sitelink_count: 8.
  - Emanuel Kayser — German scientist (1845–1927); sitelink_count: 8.
  - Helen Belyea — Canadian geologist; sitelink_count: 10.
  - Julia Anna Gardner — American geologist (1882–1960); sitelink_count: 9.
  - Ethel Skeat — English stratigrapher, invertebrate paleontologist, and geologist; sitelink_count: 5.
  - Nikolay Shatsky — Soviet geologist (1895–1960); sitelink_count: 12.
  - Wilhelm Salomon-Calvi — German paleontologist (1868–1941); sitelink_count: 6.
  - Charles Elmer Resser — American paleontologist (1889–1943); sitelink_count: 5.
  - Perceval de Loriol — Swiss paleontologist (1828–1908); sitelink_count: 7.
  - Jerzy Dzik — Polish paleontologist; sitelink_count: 6.
  - Tove Birkelund — Danish geologist (1928–1986); sitelink_count: 6.
  - Richard Foster Flint — American geologist (1902–1976); sitelink_count: 8.
  - Augusto Gansser-Biaggi — Swiss geologist (1910–2012); sitelink_count: 10.
  - Stig Bergström — Swedish paleontologist and geologist; sitelink_count: 5.
  - Wilhelm von Branca — German geologist and paleontologist (1844–1928); sitelink_count: 9.
- The listed occupations for these figures in the source include geologist, paleontologist, stratigrapher, archaeologist, prehistorian, earth scientist, and related roles. Citizenship codes were provided in the source; readable national descriptors are used above when present.

### Methods and Techniques within Stratigraphy
- Biostratigraphy: Uses fossil content to determine relative ages of rock strata. Listed with sitelink_count: 35.
- Chronostratigraphy: Focuses on relative time relations and ages of rock layers (sitelink_count: 27).
- Lithostratigraphy: Establishes stratigraphical units by lithologic criteria (sitelink_count: 25).
- Sequence stratigraphy: Analyzes groups of sedimentary deposits to interpret depositional sequences (sitelink_count: 10).
- Magnetostratigraphy: Employs magnetic properties of rocks for dating sedimentary and volcanic sequences (sitelink_count: 15).
- Chemostratigraphy: Uses chemical signatures as a technique and concept in geological stratigraphy (sitelink_count: 6).

### Cross-disciplinary Links
- Archaeological stratigraphy is explicitly listed, indicating stratigraphy's formal application within archaeological practice as a specialty.
- Stratigraphy is referenced within broader categories such as academic discipline and field of study, reflecting its role in formal education and research programs.

### Metadata and Structured Properties
- Aliases: stratigraphic geology.
- Sitelink_count: 80 (aggregate count of linked resources in the data provided).
- Wikipedia title: Stratigraphy.
- Wikidata description: study of rock layers and the layering process.
- SEO data: Not available in the provided material.

### Notes on Redundancies in Source Listing
- Biostratigraphy appears both as a contained subsidiary and as a parent-listed related field; the source lists the same description and sitelink_count (35) in both places.

### Sources and Attribution
- All facts, relationships, counts, descriptors, and dates in this entry are drawn solely from the provided source material. No external sources or inferred facts were used.

## References

1. [Source](https://github.com/JohnMarkOckerbloom/ftl/blob/master/data/wikimap)
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5. [Source](https://www.abs.gov.au/AUSSTATS/abs@.nsf/DetailsPage/1297.02008?OpenDocument)
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8. KBpedia
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10. All Science Journal Classification Codes
11. [OpenAlex](https://docs.openalex.org/download-snapshot/snapshot-data-format)