Paleontology and Fossil Preservation
56 Questions
1 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the term for the study of fossilized organisms, their life, and their environments?

  • Geochronology
  • Sedimentology
  • Paleoecology (correct)
  • Taphonomy

Which of the following represents physical remains in the context of fossils?

  • Shells and bones (correct)
  • Mineral replacements
  • Tracks and trails
  • Biomarkers

In the hierarchical classification of life, which level comes directly after Kingdom?

  • Domain
  • Family
  • Class
  • Phylum (correct)

What does Taphonomy primarily study?

<p>The changes between an organism’s death and its discovery as a fossil (A)</p> Signup and view all the answers

Which of the following provides evidence of prehistoric life, qualifying it as a fossil?

<p>Any object that provides evidence of prehistoric life (B)</p> Signup and view all the answers

What is the primary process involved in mummification?

<p>Dehydration/desiccation (A)</p> Signup and view all the answers

What condition is most conducive to the preservation of altered soft parts?

<p>Anoxia (oxygen depletion) (D)</p> Signup and view all the answers

What term describes rich fossil deposits with exceptional preservation?

<p>Fossil Lagerstätten (A)</p> Signup and view all the answers

Which mineral is commonly found unaltered in the hard parts of brachiopods and Paleozoic corals?

<p>Calcite (LMC) (B)</p> Signup and view all the answers

Which of the following organisms typically have hard parts made of aragonite?

<p>Modern corals (B)</p> Signup and view all the answers

What is the process where the crystal structure of a mineral changes without altering its chemical composition?

<p>Recrystallization (B)</p> Signup and view all the answers

What is left behind after volatile elements are removed from a fossil due to heat and pressure in carbonization?

<p>A carbon film (A)</p> Signup and view all the answers

What process involves the infilling of the pores in a skeleton with minerals that precipitate out of fluids?

<p>Permineralization (Petrification) (C)</p> Signup and view all the answers

Which mineral commonly replaces original skeletal material in fossils through the process of replacement?

<p>Dolomite (A)</p> Signup and view all the answers

Under what environmental conditions does pyrite form during the replacement process in fossils?

<p>Anoxic conditions (C)</p> Signup and view all the answers

What type of fossil is formed when the original shell dissolves away, leaving a void?

<p>A mold (A)</p> Signup and view all the answers

Which type of fossil mold preserves only internal features of the organism?

<p>Steinkern (D)</p> Signup and view all the answers

Which type of fossil mold provides a full replica of both internal and external features?

<p>Cast (C)</p> Signup and view all the answers

What are fossilized bacterial structures built by cyanobacteria called?

<p>Stromatolites (B)</p> Signup and view all the answers

In what type of environment are stromatolites commonly formed?

<p>High salinity, high water temperature, strong currents (C)</p> Signup and view all the answers

What are tracks, trails, and burrows examples of?

<p>Trace fossils (A)</p> Signup and view all the answers

Which of the following is a role of endosymbionts in larger foraminifera?

<p>Removing waste products (A)</p> Signup and view all the answers

Which of the following test types involves the foraminifera taking particles and gluing them together?

<p>Agglutinated (D)</p> Signup and view all the answers

What is the structure of crystals in the Hyaline test type?

<p>Perpendicular to test walls (B)</p> Signup and view all the answers

Which foraminifera group lacks a test and, as a result, has a poor fossil record?

<p>Allogromiida (D)</p> Signup and view all the answers

From what time period are the Texturlariida?

<p>Ordovician-Recent (C)</p> Signup and view all the answers

What key feature defines the Fusulinina?

<p>They were the first to form their own shell (D)</p> Signup and view all the answers

During which period did the planktonic Globigerinida emerge?

<p>Jurassic (C)</p> Signup and view all the answers

What type of test is characteristic of the Textulariina?

<p>Agglutinated (C)</p> Signup and view all the answers

What is a notable characteristic of foraminifera belonging to the Fusulinina?

<p>They often contain photosynthetic endosymbionts (A)</p> Signup and view all the answers

Which foraminifera group is known for its distinctive coiling pattern and porcelaneous test?

<p>Miliolina (B)</p> Signup and view all the answers

What are coprolites?

<p>Fossilized dung (A)</p> Signup and view all the answers

What is the term for chemical evidence of past life?

<p>Biomarkers (D)</p> Signup and view all the answers

What organic compound, derived from bacterial cell walls, can be found as a biomarker?

<p>Hopane (C)</p> Signup and view all the answers

What is the study of the processes that occur from the death of an organism to its final burial?

<p>Biostratinomy (D)</p> Signup and view all the answers

What process involves the removal of joints in a deceased organism?

<p>Disarticulation (D)</p> Signup and view all the answers

Through what process can complete arthropods and echinoderms be preserved?

<p>Obrution (A)</p> Signup and view all the answers

What is the term for wear on fossils caused by transport?

<p>Abrasion (A)</p> Signup and view all the answers

What term describes fossils found in the same environment they lived in?

<p>Indigenous (A)</p> Signup and view all the answers

What is the term for fossils from older rocks mixed with new sediments?

<p>Reworked (C)</p> Signup and view all the answers

What factor controls a species' presence and abundance in an ecosystem?

<p>Limiting factor (B)</p> Signup and view all the answers

Which of these is considered a metabolic factor affecting paleoecology?

<p>Temperature (C)</p> Signup and view all the answers

What is the term for organisms that live on the surface of a sediment?

<p>Epifauna (C)</p> Signup and view all the answers

What characteristic makes some fossil groups useful markers for short geological time periods?

<p>Rapid rates of speciation and extinction (C)</p> Signup and view all the answers

What is a key advantage of pelagic organisms in the context of fossil records?

<p>They are broadly distributed across the world’s oceans (A)</p> Signup and view all the answers

What part of a cephalopod shell regulates buoyancy?

<p>Siphuncle (C)</p> Signup and view all the answers

What is the outermost organic layer of a molluscan shell called?

<p>Periostracum (B)</p> Signup and view all the answers

What evolutionary trend is observed in cephalopod shells during the Ordovician period?

<p>Trend towards tightly coiled shells (A)</p> Signup and view all the answers

What kind of coiling do most living and fossil cephalopods exhibit?

<p>Planispiral (D)</p> Signup and view all the answers

What function did chambered shells provide for cephalopods?

<p>Buoyancy (A)</p> Signup and view all the answers

What problem did cephalopods face concerning their chambered shells?

<p>Aligning center of buoyancy and gravity (D)</p> Signup and view all the answers

What is the purpose of cameral deposits in cephalopod shells?

<p>To adjust weight distribution (B)</p> Signup and view all the answers

What is a brevicone shell shape?

<p>A short, conical shell (B)</p> Signup and view all the answers

What effect does a tighter coil (involute) have on a cephalopod shell?

<p>Improves stability (A)</p> Signup and view all the answers

What is the formula for calculating the whorl expansion rate (W)?

<p>$W = (b/a)^2$ (D)</p> Signup and view all the answers

Where do benthic foraminifera typically live?

<p>On or in sediment surfaces, or attached to plants/algae (C)</p> Signup and view all the answers

Flashcards

Hierarchical Classification

A system for organizing life from broad to specific categories.

Taphonomy

The study of how organisms decay and become fossilized.

Fossil

Any evidence of prehistoric life.

Physical Remains (Fossils)

Preserved remains like shells, bones, or hard parts.

Signup and view all the flashcards

Mineral Replacement (Fossils)

Fossils where original tissues are replaced by minerals.

Signup and view all the flashcards

Unaltered Soft Parts

Organic tissues remain unchanged except for water loss, preserving the original structure.

Signup and view all the flashcards

Altered Soft Parts

Soft tissues undergo chemical changes such as carbonization or mineralization during preservation.

Signup and view all the flashcards

Fossil Lagerstätten

Exceptional fossil sites with great preservation of soft tissues and articulated hard parts.

Signup and view all the flashcards

Unaltered Hard Parts

Original mineral composition remains intact in the fossilized hard parts.

Signup and view all the flashcards

Recrystallization

The crystal structure changes, but the chemical composition remains the same.

Signup and view all the flashcards

Carbonization

Heat and pressure remove volatile elements, leaving a carbon film.

Signup and view all the flashcards

Permineralization (Petrification)

Pores of the skeleton are infilled with minerals that precipitate out of fluids, turning it to stone.

Signup and view all the flashcards

Anoxia Conditions

Depletion of oxygen, aiding in soft tissue preservation.

Signup and view all the flashcards

Replacement Fossilization

The original skeleton dissolves and is replaced by new minerals.

Signup and view all the flashcards

Dolomite in Fossilization

A carbonate mineral that can replace original skeletal material during fossilization.

Signup and view all the flashcards

Leached Fossil

A fossil formed when the original shell dissolves, leaving a void or mineral filling.

Signup and view all the flashcards

Steinkern

A fossil mold showing only internal features, often muscle attachments.

Signup and view all the flashcards

Cast Fossil

A fossil that preserves both internal and external features, creating a full replica.

Signup and view all the flashcards

Replica Fossil

A fossil that preserves only external features of the original organism/shell.

Signup and view all the flashcards

Stromatolites

Fossilized bacterial structures built by cyanobacteria, often in domes.

Signup and view all the flashcards

Thrombolites

Unlaminated, clotted microbial build-ups unlike layered stromatolites.

Signup and view all the flashcards

Index Fossil Traits

Rapid evolution, wide distribution, abundance, and easy identification make them useful for dating rocks.

Signup and view all the flashcards

Demersal Predators

Refers to predators that live near or on the seafloor.

Signup and view all the flashcards

Endocones

Internal deposits that balance buoyancy in cephalopod shells.

Signup and view all the flashcards

Beaded Calcified Siphuncle

Reinforced structures regulating gas exchange in cephalopod shells.

Signup and view all the flashcards

Cameral Deposits

Mineralized deposits within shell chambers to adjust weight distribution.

Signup and view all the flashcards

Brevicone

Short, conical cephalopod shell; stable but slower.

Signup and view all the flashcards

Involute Coiling

Tight coils in cephalopod shells improve stability.

Signup and view all the flashcards

Evolute Coiling

Looser coils enhances maneuverability in cephalopod shells.

Signup and view all the flashcards

Whorl Expansion Rate (W)

Ratio of the radius of two successive whorls squared. Indicates shell shape.

Signup and view all the flashcards

Planktonic Foraminifera

Planktonic forminifera live in the water column and have small, short-lived LMC shells.

Signup and view all the flashcards

Coprolites

Fossilized feces, providing insights into diet and ancient ecosystems.

Signup and view all the flashcards

Biomarkers

Chemical evidence of past life, like hopanes or cholesterol.

Signup and view all the flashcards

Biostratinomy

Changes occurring after death but before final burial.

Signup and view all the flashcards

Disarticulation

Joint separation in fossils, common without rapid burial.

Signup and view all the flashcards

Abrasion

Wear on fossils due to sediment transport.

Signup and view all the flashcards

Fossil Hash

Fossils extensively worn due to transport by strong currents.

Signup and view all the flashcards

Reorientation

Currents align shells in a preferred direction.

Signup and view all the flashcards

Bimodal Orientation

Shells pointing predominantly in two directions.

Signup and view all the flashcards

Exotic Fossils

Fossils transported from a different environment but same time period.

Signup and view all the flashcards

Reworked Fossils

Fossils from older rocks mixed into younger sediments.

Signup and view all the flashcards

Paleoecology

Study of the relationships between fossil organisms and their environments.

Signup and view all the flashcards

Limiting Factors

Factors that limit a species' presence and abundance.

Signup and view all the flashcards

Epifauna

Organisms living on the surface of a substrate.

Signup and view all the flashcards

Infauna

Organisms living within the sediment.

Signup and view all the flashcards

Turbulence

Water agitation affecting organism distribution. High in shallow environments.

Signup and view all the flashcards

Dinoflagellates

Single-celled organisms, some provide energy through photosynthesis. Endosymbionts.

Signup and view all the flashcards

Diatoms

Single-celled algae, some provide energy through photosynthesis .

Signup and view all the flashcards

Why endosymbionts?

Photosynthesis provides an energetic advantage, promoting calcification. Removal of waste.

Signup and view all the flashcards

Agglutinated test

Takes particles and glues them together to create the shell wall.

Signup and view all the flashcards

Porcelaneous test

Calcite crystals orderly arranged, shell wall is similar to porcelain

Signup and view all the flashcards

Hyaline test

Hyaline crystals are perpendicular to test walls, shell wall is 'glassy'.

Signup and view all the flashcards

Allogromiida

First foraminifera group to evolve, lacking a test; makes fossil record difficult.

Signup and view all the flashcards

Texturlariida

Foraminifera group with agglutinated tests, dating from Cambrian to recent.

Signup and view all the flashcards

Globigerinida

Planktonic foraminifera group abundant in oceans since the Jurassic period.

Signup and view all the flashcards

Miliolina

Foraminifera suborder characterized by a porcelaneous test, distinctive coiling and the presence of symbionts.

Signup and view all the flashcards

Study Notes

Hierarchical Classification of Life

  • Is arranged by: Domain, Kingdom, Phylum, Subphylum, Class, Order, Family

Taphonomy

  • Involves changes between an organism's death and its discovery as a fossil.
  • Taphonomy controls the fidelity of the fossil record.
  • It offers essential insights into the ancient environment.
  • Paleoecology studies fossilized organisms, their lives, and their environments.

Fossils

  • Fossils provide evidence of prehistoric life.
  • Types of fossils include:
  • Physical remnants like shells, bones, and hard parts.
  • Mineral replicas of bodies/skeletons.
  • Biological impressions like tracks, trails, and burrows.
  • Chemical traces like biomarkers.

Modes of Fossil Preservation

  • Listed from the least to the most information loss:
  • Unaltered soft parts.
  • Altered soft parts.
  • Unaltered hard parts.
  • Altered hard parts.
  • Leached fossils.
  • Biogenic structures.
  • Biomarkers.

Soft Part Preservation

  • Unaltered soft parts show no changes except for water loss.
  • Preservation occurs in:
  • Freezing conditions.
  • Mummification, where dehydration/desiccation removes water.
  • Conservation traps shield from decay.
  • Altered soft parts undergo carbonization or mineralization.
  • Anoxia, which is oxygen depletion.
  • Obrution, which is rapid burial.
  • Fossil Lagerstatten displays exceptional preservation of soft tissues and articulated hard parts.

Hard Part Preservation

  • Unaltered hard parts retain their original mineral composition.
  • Minerals and related organisms:
  • Calcite(LMC): Brachiopods, bryozoans, paleozoic corals, echinoderms.
  • Aragonite: Molluscs, modern corals.
  • Silica: Radiolaria, diatoms, some sponges.
  • Phosphate: Vertebrate bones, conodonts, inarticulate brachiopods. chitin/collagen - Arthropods, grapolites.
  • cellulose - Wood, plant material.
  • Altered hard parts undergo:
  • Recrystallization: alters the crystal structure without changing the chemical composition, potentially losing water.
  • Aragonite(CaCO3) transforms into LMC(CaCO3).
  • Carbonization involves removing volatile elements through heat and pressure, leaving a carbon remains ex. coal(black) or graphite(silver).
  • Permineralization inserts minerals into pores within a skeleton, turning it into stone which won't burn.
  • An example includes silicified wood.
  • Replacement: swaps the original framework with new minerals like dolomite, silica, pyrite, or limonite/goethite after dissolution.

Leached Fossils

  • Leached fossils result from the dissolution of the original shell, subsequently leaving voids, it's common in molluscs, where aragonite dissolves easily:
  • The types of fossil molds include:
  • Steinkern (core) captures internal features, muscle attachments/3D form by popping out.
  • Cast exhibits both internal and exterior features displaying a full replica and 3D.
  • Replica shows only External 3D features.
  • Mold shows only External features of shell structure and 2D form.

Biogenic Structures

  • Biostratification:
  • Stromatolites are fossilized bacterial forms built by cyanobacteria in grazer-free, high salinity environments.
  • Bacteria form microbial mats that trap carbonate mud to form low domes, growing taller upwards into stromatolites.
  • Unlaminated thrombolites are clotted microbial constructions.
  • Trace fossils include tracks, trails, burrows, and borings.
  • Coprolites consist of fossilized excrement.

Biomarkers

  • Biomarkers provide chemical evidence of life from:
  • Diagenesis of existing cells
  • Hopanepolyol that is derived from the cell walls of bacteria.
  • Hopane: Organic product of hopanepolyol
  • Cholesterol: Compound representing animal kingdoms

Biostratinomy

  • Biostratinomy covers events after death but before burial which leads to
  • The loss of biological info
  • The gain of insight into depositional settings.
  • Important Processes:
  • Disarticulation: The Scavengers remove joints and damage complete bodies
  • Abrasion: is caused by the wear from transport involving fossil hash that bivalves hold stronger
  • Abrasion can be observed by wear on the Mohs Hardness Scale

Transport of Shells

  • Key points
  • By action traction currents extensive abrasion is involved
  • With suspension minimal abrasion is shown
  • Common transport locations are:
  • Storm beds.
  • Turbidites: a flow bearing a higher density.
  • Currents that flow with higher density.

Reorientation

  • Reorientation involves the alignment of shells by currents or waves which includes:
  • Unimodal orientation: all vertices pointing the same direction
  • Current needs to flow in only single direction(s)
  • Direction is not able to be determined
  • Bimodal alignment: vertices positioned at a 180 degree separation
    • Caused by bidirectional current(s) flow shell
  • Shells flip after a threshold is met by energy in a wave or current which includes that:
  • The current overcomes the threshold to flip the shell.
  • Horizontal alignment is waves are strong enough for the shell
  • Strong bimodal alignment indicates large wave action

Dissolution

  • Shells dissolve in cold/freshwater
  • Can also occur before burial

Transportation Types and Key Information

  • Indigenous
    • Found in normal environment
    • Still has close information
  • Exotic
    • Transported from normal environment
    • Deposits from storms
  • Reworked (remanie)
    • Fossils from old rocks mixed with new sediments
    • Misleads age dating

Paleoecology

  • Covers
    • Environmental change
    • Understanding evolution and limits
    • Explains modern ecosystems adapting
    • Complex ecosystem development
  • Key limiting factors consist of categories with important factors like
    • Sedimentologic has grain size
    • Metabolic has oxygen
    • Combination has depth

Sedimentologic

  • Sedimentologic has key details like:
    • Grain size which influence the type abundance of life
      • Epifauna is a surface layer
      • Sand is more mobile
  • Substrate relating to grain cohesiveness
    • Important factor impacting the benthos and infauna
    • Epifauna surface is mobile sessile attached
    • Infuana is a burrow tunnels -Water agitation
    • Common in water area Turbidity is for suspended materials that effect respiration

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

GEOL 337 Lecture Notes: Fossil Preservation & Paleoecology PDF

Description

Explore the study of fossils, including fossilized organisms and prehistoric life. Learn about the classification of life, taphonomy, and the processes of mummification and fossil preservation. Investigate the minerals found in fossils and the conditions that favor their preservation.

More Like This

Taphonomy and Fighting Dinosaurs
401 questions

Taphonomy and Fighting Dinosaurs

AppealingDemantoid3464 avatar
AppealingDemantoid3464
Paleontology 101: Fossil Types and Formation
25 questions

Paleontology 101: Fossil Types and Formation

DurableAlien857 avatar
DurableAlien857
Taphonomy: The Path to Becoming a Fossil
13 questions

Taphonomy: The Path to Becoming a Fossil

WorthyDalmatianJasper7941 avatar
WorthyDalmatianJasper7941
Paleontology
56 questions

Paleontology

SecureMothman avatar
SecureMothman
Use Quizgecko on...
Browser
Open
Browser
Browser