Name: sediment biomarkers for past climate records
Uploaded: 2023-04-30T06:49:01.000Z
Duration: 8 min 28 s
Channel: JoVE

K12 Standards

north-carolina-k-12-science-standard-course-of-study

NC K-12 Science Standard Course of Study

9-12

Earth and Environmental Science

Earth's Systems

ESS.EES.3.3

an-overview-of-bgdgt-biomarker-analysis-for-paleoclimatology

An Overview of bGDGT Biomarker Analysis for Paleoclimatology

<div class="chapter_text" id="script_0">
Organic compounds called biomarkers can be used in Earth Science as paleothermometers to relate information on climates and environments of the past.
Living organisms produce these biomarkers, which provide us with information about the environment in which they lived. They can act as a&#160;proxy&#160;to tell us information about past events, like the Earth&#8217;s temperature millions of years ago.
Terrestrial paleotemperature can be analyzed using biomarkers found in sediment from fresh-water basins. One key class of these biomarkers are branched glycerol dialkyl glycerol tetraethers, or branched GDGTs.
This video will introduce the area of study, called paleoclimatology, which investigates past changes in fresh-water environments over hundreds of millions of year. This helps elucidate current and future climate and environmental changes.
</div>
<div class="chapter_text" id="script_1">
Sediments accumulate over geologic time, due to fluid movement and gravity, in sedimentary basins, or low areas in the Earth&#8217;s crust. Sedimentary basins include oceans, which collect marine sediment, or lakes, which collect lacustrine sediment. Marine and lacustrine basins contain different types of organisms, driven in large part by the difference in salinity between them. Thus, marine and lacustrine basins contain different biomarkers.
Branched GDGTs are thought to be membrane-spanning lipids of anaerobic acidobacteria. Research suggests that the producing organisms change membrane properties in response to changing temperature.
This change is caused by the transformation of methylated sites on the branched GDGT&#8217;s to cyclized sites at colder temperatures, thereby enhancing membrane fluidity. This change in structure can then be correlated to temperature through a proxy. Proxies are measureable physical phenomena that are correlated to immeasurable variable.
This proxy relates the number of methylations or MBT, and cyclizations, or CBT, in the biomarker to temperature. An experimentally-derived equation can relate MBT and CBT to the past Mean Annual Air Temperature.
</div>
<div class="chapter_text" id="script_2">
To study the relationship between branched GDGT biomarkers and soil temperature, lacustrine sediment must be collected, extracted by one of three techniques, purified, and analyzed.
To begin studying the relationship between branched GDGT biomarkers and soil temperature, the lipid molecules are first extracted from lacustrine sediments, using a variety of techniques. Extraction via sonication is the simplest and least expensive method of obtaining the total lipid extract, or TLE, from a sediment sample. For this, an ultrasonic bath is used to agitate the sample in a vial containing organic solvent. A mixture of methanol and dichloromethane is used to extract biomarkers with a wide range of polarities. Another extraction technique utilizes Soxhlet extraction. A Soxhlet extractor enables the reflux, or continuous cycling, of organic solvent from a round-bottom flask upward into a condenser, which is cooled by cold water and returned. The condensed solvent falls into a glass fiber thimble containing the sample. Once full, the chamber siphons the organic solvent back into the round-bottom flask, enabling continuous extraction over time.
This technique is helpful in the extraction of large sediment masses, and the preparation of large volumes of standards for instrument calibration. Finally, accelerated solvent extraction, or ASE, is a trademarked method of extraction that utilizes high temperature and pressure to increase the kinetics of the extraction process. The ASE instrument holds up to 24 individual samples, and allows for precise control of all parameters in the extraction process. Due to its speed and simplicity of use, ASE is commonly used as the standard method of solvent extraction.
</div>
<div class="chapter_text" id="script_3">
Once the lipid sample is extracted using one of these techniques, it is purified in preparation for analysis. Typically, silica gel column chromatography is used to purify the lipid sample based on its polarity. For this, a small glass column is loaded with a fine powder of silica, called a gel. The column is then saturated with an apolar solvent, typically hexane, and then the sample loaded on the top. The separation of the extract is based on the affinity of the target compound for either the solid phase or the solvent phase.
Polar compounds, in this case branched GDGT&#39;s, are more attracted to the polar silica than the apolar hexane. Thus, the apolar compounds, such as hydrocarbons, the mid-polar compounds, such as ketones and alcohols, and the highly polar compounds, will travel the column at different rates and in response to solvents of increasing polarity.
The eluents are then collected in separate fractions.
The purified GDGT&#39;s are then analyzed using high performance liquid chromatography coupled to a mass spectrometer, or LC-MS. LC-MS first separates the compounds, and then analyzes them based on their mass-to-charge ratio.
This enables the determination of the relative concentration of each type of GDGT using the area under the curve for the selected mass ion. MBT is calculated as the fraction of the group 1 molecules to the total.
CBT is then calculated as a negative log using molecules in groups 1 and 2. MBT and CBT are then plugged into an experimentally-derived equation, in order to arrive at a paleotemperature determination.
</div>
<div class="chapter_text" id="script_4">
The determination of paleotemperature using biomarker proxies is useful in a range of applications in earth science.
First, paleothermometry enables the determination of the Earth&#39;s temperature over long periods of time. Using various techniques, the temperature of Earth has been estimated as far back as 500 million years. This tells us the envelope of temperature within which different forms of life evolved and informs investigations of the effects of temperature on Earth&#39;s biosphere, hydrosphere, lithosphere, and atmosphere in the past, and by extension, the future.
More recent trends in the Earths temperature can also be quantified against records constructed using paleothermometry. The Earths surface temperature has increased by nearly 1 degree from 1850 to the present with an accentuated warming trend in the last two decades. To understand the anthropogenic impact on global climate, accurate paleoclimate records must be developed and used as context.
</div>
<div class="chapter_text" id="script_5">
You&#39;ve just watched JoVE&#39;s Overview of Branched Glycerol Dialkyl Glycerol Tetraether Paleothermometry. You should now understand how the branched GDGT biomarkers are used, and the overall technique of extracting and purifying them. The following videos in this series will go into more detail about this complex process.
Thanks for watching!
</div>

an overview of bgdgt biomarker analysis for paleoclimatology

Source: Laboratory of Jeff Salacup - University of Massachusetts Amherst
Throughout this series of videos, natural samples were extracted and purified in search of organic compounds, called biomarkers, that can relate information on climates and environments of the past. One of the samples analyzed was sediment. Sediments accumulate over geologic time in basins, depressions in the Earth into which sediment flows through the action of fluid (water or air), movement, and gravity. Two main types of basins exist, marine (oceans and seas) and lacustrine (lakes). As one might guess, very different types of life live in these settings, driven in large part by the difference in salinity between them. Over the last few decades, organic geochemists discovered a toolbox of biomarker proxies, or compounds that can be used to describe climate or environment, some of which work in marine environments and some of which work in lacustrine. We turn our attention here to the lacustrine realm and branched glycerol dialkyl glycerol tetraethers (Figure 1).
In this section we focus on analysis of terrestrial paleotemperature using branched glycerol dialkyl glycerol tetrathers (Figure 1; brGDGTs) and the MBT/CBT proxy. This proxy was initially described by Weijers et al.1 and is based on the distribution of ring and branch structures in brGDGTs. They found that the cyclization of branched tetraethers (CBT) was directly related to soil pH.
CBT = -log ((Ib + IIb) / (I + II))
And that the methylation of branched tetraethers (MBT) was determined by mean annual air temperature (MAAT) and, to a lesser extent, soil pH.
MBT = (I + Ib + Ic) / (I + Ib + Ic) + (II + IIb + IIc) + (III + IIIb + IIIc)
Thus, taken together and calibrated, MBT/CBT relates the distribution of brGDGTs to both soil temperature and pH.
MBT = 0.122 + (0.187 x CBT) + (0.020 x MAAT)
Branched GDGTs are thought to be membrane spanning lipids and their production was initially attributed to anaerobic Acidobacteria bacteria living in soils and peat2-5, but subsequent work suggested they could also be produced in oxic and anoxic lake and marine water columns and sediments6-9. The hypothesis holds that Acidobacteria transform sites of methylation into cyclizations in response to lowering temperature in order to increase unsaturation (cyclization effectively removes two hydrogen atoms) and maintain membrane fluidity (by analogy, saturated fat (butter) is a solid a room temperature while unsaturated fat (olive oil) is a liquid), but branched GDGTs have not yet been identified as the main membrane lipids in Acidobacteria cultures. Thus their exact provenance is unknown.
Calibration of branched GDGTs to environmental variables (temperature, pH, salinity, precipitation, etc.) is a topic of widespread research. Organic geochemistry laboratories all over the world are involved in the task of developing both global1,10 and regional11-13 calibrations between branched GDGTs and (primarily) temperature. Thus, the equations given above are regularly being refined and perfected.
Branched GDGTs are usually extracted from lacustrine sediments, although coastal marine sediments have also been investigated. The extracts undergo a silica gel column to purify the GDGTs from other compounds which may not be LC amenable or that may co-elute with GDGTs chromatographically. The GDGTs come out in the polar fraction that elutes in methanol.
Once the total lipid extract is purified, the extracted and purified sample is run on a high performance liquid chromatograph coupled to a chemical ionization mass spectrometer. The relative concentration of the GDGTs is determined by obtaining the area under the curve for the selected mass ion (m/z; Figure 1) for each of the compounds on computer software designed for just this purpose (such as Agilent Chemstation). These areas are then put into the selected calibration equation in order to arrive at a paleotemperature determination.
<img alt="Branched GDGTs diagram showing chemical structures and mass spectrometry data (m/z values)." src="/files/ftp_upload/10256/10256fig1.jpg" data-altupdatedat="1761830439000" data-alt="Figure 1"> 
Figure 1. Structures of the branched GDGTs used for calculating temperature via MBT/CBT proxy (used with permission of Dr. Isla Castañeda, who produced the image). <a href="https://www.jove.com/files/ftp_upload/10256/10256fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<div class="chapter_text" id="script_0">
Organic compounds called biomarkers can be used in Earth Science as paleothermometers to relate information on climates and environments of the past.
Living organisms produce these biomarkers, which provide us with information about the environment in which they lived. They can act as a proxy to tell us information about past events, like the Earth’s temperature millions of years ago.
Terrestrial paleotemperature can be analyzed using biomarkers found in sediment from fresh-water basins. One key class of these biomarkers are branched glycerol dialkyl glycerol tetraethers, or branched GDGTs.
This video will introduce the area of study, called paleoclimatology, which investigates past changes in fresh-water environments over hundreds of millions of year. This helps elucidate current and future climate and environmental changes.
</div>
<div class="chapter_text" id="script_1">
Sediments accumulate over geologic time, due to fluid movement and gravity, in sedimentary basins, or low areas in the Earth’s crust. Sedimentary basins include oceans, which collect marine sediment, or lakes, which collect lacustrine sediment. Marine and lacustrine basins contain different types of organisms, driven in large part by the difference in salinity between them. Thus, marine and lacustrine basins contain different biomarkers.
Branched GDGTs are thought to be membrane-spanning lipids of anaerobic acidobacteria. Research suggests that the producing organisms change membrane properties in response to changing temperature.
This change is caused by the transformation of methylated sites on the branched GDGT’s to cyclized sites at colder temperatures, thereby enhancing membrane fluidity. This change in structure can then be correlated to temperature through a proxy. Proxies are measureable physical phenomena that are correlated to immeasurable variable.
This proxy relates the number of methylations or MBT, and cyclizations, or CBT, in the biomarker to temperature. An experimentally-derived equation can relate MBT and CBT to the past Mean Annual Air Temperature.
</div>
<div class="chapter_text" id="script_2">
To study the relationship between branched GDGT biomarkers and soil temperature, lacustrine sediment must be collected, extracted by one of three techniques, purified, and analyzed.
To begin studying the relationship between branched GDGT biomarkers and soil temperature, the lipid molecules are first extracted from lacustrine sediments, using a variety of techniques. Extraction via sonication is the simplest and least expensive method of obtaining the total lipid extract, or TLE, from a sediment sample. For this, an ultrasonic bath is used to agitate the sample in a vial containing organic solvent. A mixture of methanol and dichloromethane is used to extract biomarkers with a wide range of polarities. Another extraction technique utilizes Soxhlet extraction. A Soxhlet extractor enables the reflux, or continuous cycling, of organic solvent from a round-bottom flask upward into a condenser, which is cooled by cold water and returned. The condensed solvent falls into a glass fiber thimble containing the sample. Once full, the chamber siphons the organic solvent back into the round-bottom flask, enabling continuous extraction over time.
This technique is helpful in the extraction of large sediment masses, and the preparation of large volumes of standards for instrument calibration. Finally, accelerated solvent extraction, or ASE, is a trademarked method of extraction that utilizes high temperature and pressure to increase the kinetics of the extraction process. The ASE instrument holds up to 24 individual samples, and allows for precise control of all parameters in the extraction process. Due to its speed and simplicity of use, ASE is commonly used as the standard method of solvent extraction.
</div>
<div class="chapter_text" id="script_3">
Once the lipid sample is extracted using one of these techniques, it is purified in preparation for analysis. Typically, silica gel column chromatography is used to purify the lipid sample based on its polarity. For this, a small glass column is loaded with a fine powder of silica, called a gel. The column is then saturated with an apolar solvent, typically hexane, and then the sample loaded on the top. The separation of the extract is based on the affinity of the target compound for either the solid phase or the solvent phase.
Polar compounds, in this case branched GDGT's, are more attracted to the polar silica than the apolar hexane. Thus, the apolar compounds, such as hydrocarbons, the mid-polar compounds, such as ketones and alcohols, and the highly polar compounds, will travel the column at different rates and in response to solvents of increasing polarity.
The eluents are then collected in separate fractions.
The purified GDGT's are then analyzed using high performance liquid chromatography coupled to a mass spectrometer, or LC-MS. LC-MS first separates the compounds, and then analyzes them based on their mass-to-charge ratio.
This enables the determination of the relative concentration of each type of GDGT using the area under the curve for the selected mass ion. MBT is calculated as the fraction of the group 1 molecules to the total.
CBT is then calculated as a negative log using molecules in groups 1 and 2. MBT and CBT are then plugged into an experimentally-derived equation, in order to arrive at a paleotemperature determination.
</div>
<div class="chapter_text" id="script_4">
The determination of paleotemperature using biomarker proxies is useful in a range of applications in earth science.
First, paleothermometry enables the determination of the Earth's temperature over long periods of time. Using various techniques, the temperature of Earth has been estimated as far back as 500 million years. This tells us the envelope of temperature within which different forms of life evolved and informs investigations of the effects of temperature on Earth's biosphere, hydrosphere, lithosphere, and atmosphere in the past, and by extension, the future.
More recent trends in the Earths temperature can also be quantified against records constructed using paleothermometry. The Earths surface temperature has increased by nearly 1 degree from 1850 to the present with an accentuated warming trend in the last two decades. To understand the anthropogenic impact on global climate, accurate paleoclimate records must be developed and used as context.
</div>
<div class="chapter_text" id="script_5">
You've just watched JoVE's Overview of Branched Glycerol Dialkyl Glycerol Tetraether Paleothermometry. You should now understand how the branched GDGT biomarkers are used, and the overall technique of extracting and purifying them. The following videos in this series will go into more detail about this complex process.
Thanks for watching!
</div>

Source: Laboratory of Jeff Salacup&#160;- University of Massachusetts Amherst
Throughout this series of videos, natural samples were extracted and ...

Organic compounds called biomarkers can be used in Earth Science as paleothermometers to relate information on climates and environments of the past.Living organisms produce these biomarkers, which provide us with information about the environment in which they lived. They can act as a?proxy?to tell us information about past events, like the Earth?s temperature millions of years ago.Terrestrial paleotemperature can be analyzed using biomarkers found in sediment from fresh-water basins. One key class of these biomarkers are branched glycerol dialkyl glycerol tetraethers, or branched GDGTs.This video will introduce the area of study, called paleoclimatology, which investigates past changes in fresh-water environments over hundreds of millions of year. This helps elucidate current and future climate and environmental changes.Sediments accumulate over geologic time, due to fluid movement and gravity, in sedimentary basins, or low areas in the Earth?s crust. Sedimentary basins include oceans, which collect marine sediment, or lakes, which collect lacustrine sediment. Marine and lacustrine basins contain different types of organisms, driven in large part by the difference in salinity between them. Thus, marine and lacustrine basins contain different biomarkers.Branched GDGTs are thought to be membrane-spanning lipids of anaerobic acidobacteria. Research suggests that the producing organisms change membrane properties in response to changing temperature.This change is caused by the transformation of methylated sites on the branched GDGT?s to cyclized sites at colder temperatures, thereby enhancing membrane fluidity. This change in structure can then be correlated to temperature through a proxy. Proxies are measureable physical phenomena that are correlated to immeasurable variable.This proxy relates the number of methylations or MBT, and cyclizations, or CBT, in the biomarker to temperature. An experimentally-derived equation can relate MBT and CBT to the past Mean Annual Air Temperature.To study the relationship between branched GDGT biomarkers and soil temperature, lacustrine sediment must be collected, extracted by one of three techniques, purified, and analyzed.To begin studying the relationship between branched GDGT biomarkers and soil temperature, the lipid molecules are first extracted from lacustrine sediments, using a variety of techniques. Extraction via sonication is the simplest and least expensive method of obtaining the total lipid extract, or TLE, from a sediment sample. For this, an ultrasonic bath is used to agitate the sample in a vial containing organic solvent. A mixture of methanol and dichloromethane is used to extract biomarkers with a wide range of polarities. Another extraction technique utilizes Soxhlet extraction. A Soxhlet extractor enables the reflux, or continuous cycling, of organic solvent from a round-bottom flask upward into a condenser, which is cooled by cold water and returned. The condensed solvent falls into a glass fiber thimble containing the sample. Once full, the chamber siphons the organic solvent back into the round-bottom flask, enabling continuous extraction over time.This technique is helpful in the extraction of large sediment masses, and the preparation of large volumes of standards for instrument calibration. Finally, accelerated solvent extraction, or ASE, is a trademarked method of extraction that utilizes high temperature and pressure to increase the kinetics of the extraction process. The ASE instrument holds up to 24 individual samples, and allows for precise control of all parameters in the extraction process. Due to its speed and simplicity of use, ASE is commonly used as the standard method of solvent extraction.Once the lipid sample is extracted using one of these techniques, it is purified in preparation for analysis. Typically, silica gel column chromatography is used to purify the lipid sample based on its polarity. For this, a small glass column is loaded with a fine powder of silica, called a gel. The column is then saturated with an apolar solvent, typically hexane, and then the sample loaded on the top. The separation of the extract is based on the affinity of the target compound for either the solid phase or the solvent phase.Polar compounds, in this case branched GDGT's, are more attracted to the polar silica than the apolar hexane. Thus, the apolar compounds, such as hydrocarbons, the mid-polar compounds, such as ketones and alcohols, and the highly polar compounds, will travel the column at different rates and in response to solvents of increasing polarity.The eluents are then collected in separate fractions.The purified GDGT's are then analyzed using high performance liquid chromatography coupled to a mass spectrometer, or LC-MS. LC-MS first separates the compounds, and then analyzes them based on their mass-to-charge ratio.This enables the determination of the relative concentration of each type of GDGT using the area under the curve for the selected mass ion. MBT is calculated as the fraction of the group 1 molecules to the total.CBT is then calculated as a negative log using molecules in groups 1 and 2. MBT and CBT are then plugged into an experimentally-derived equation, in order to arrive at a paleotemperature determination.The determination of paleotemperature using biomarker proxies is useful in a range of applications in earth science.First, paleothermometry enables the determination of the Earth's temperature over long periods of time. Using various techniques, the temperature of Earth has been estimated as far back as 500 million years. This tells us the envelope of temperature within which different forms of life evolved and informs investigations of the effects of temperature on Earth's biosphere, hydrosphere, lithosphere, and atmosphere in the past, and by extension, the future.More recent trends in the Earths temperature can also be quantified against records constructed using paleothermometry. The Earths surface temperature has increased by nearly 1 degree from 1850 to the present with an accentuated warming trend in the last two decades. To understand the anthropogenic impact on global climate, accurate paleoclimate records must be developed and used as context.You've just watched JoVE's Overview of Branched Glycerol Dialkyl Glycerol Tetraether Paleothermometry. You should now understand how the branched GDGT biomarkers are used, and the overall technique of extracting and purifying them. The following videos in this series will go into more detail about this complex process.Thanks for watching!

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sediment biomarkers for past climate records

Sediment biomarkers can record past climate conditions, and branched GDGTs are one example used to study temperature in freshwater basins. These organic compounds are extracted from natural samples, purified, and then measured to help reconstruct environments from the past. In paleoclimatology, scientists use these records to better understand climate change over time.

Sediments build up over geologic time in sedimentary basins, which are low areas in the Earth’s crust where material is carried by water, air, movement, and gravity. Two main basin types are marine basins, such as oceans and seas, and lacustrine basins, such as lakes. Because these settings support different organisms and often differ in salinity, they contain different biomarkers.

Branched glycerol dialkyl glycerol tetraethers, or branched GDGTs, are studied in lacustrine sediment as paleothermometers. They are linked to the MBT/CBT proxy, which uses the number of methylation and cyclization features in the molecules. CBT, or cyclization of branched tetraethers, has been related to soil pH, while MBT, or methylation of branched tetraethers, is linked mainly to mean annual air temperature and also to soil pH.

Branched GDGTs are thought to be membrane-spanning lipids made by anaerobic Acidobacteria, which are bacteria found in soils and peat. Some research also suggests these compounds can form in oxic and anoxic lake and marine water columns and sediments. Scientists think colder conditions may shift methylated sites toward cyclized sites to help maintain membrane fluidity, but the exact source of the lipids is still not fully known.

To study these biomarkers, lacustrine sediments are collected, extracted, purified, and analyzed. The total lipid extract can be obtained by sonication, Soxhlet extraction, or accelerated solvent extraction, also called ASE. Sonication is the simplest and least expensive method, Soxhlet uses continuous solvent cycling, and ASE uses high temperature and pressure and is often used as the standard method because it is fast and easy to control.

After extraction, the sample is usually purified with silica gel column chromatography. In this step, the sample moves through silica using solvents of increasing polarity. Polar branched GDGTs are retained differently from apolar, mid-polar, and highly polar compounds, so the eluents are collected in separate fractions. The purified GDGTs are then ready for analysis.

The final measurement uses high performance liquid chromatography coupled to mass spectrometry, or LC-MS. This method separates the compounds and measures them by mass-to-charge ratio, or m/z. The relative abundance of each GDGT is calculated from the area under the curve for the selected ion, and those values are entered into the calibration equation to estimate paleotemperature.

Branched GDGT paleothermometry helps scientists estimate Earth’s temperature over very long time spans. Temperature records have been reconstructed as far back as 500 million years, which helps show the range of conditions in which life evolved. These records also provide context for modern warming, including the rise in Earth’s surface temperature since 1850 and the stronger warming trend seen in recent decades.

Sediment Biomarkers for Past Climate Records

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Sediment biomarkers can record past climate conditions, and branched GDGTs are one example used to study temperature in freshwater basins. These organic compounds are extracted from natural samples, purified, and then measured to help reconstruct environments from the past. In paleoclimatology, scientists use these records to better understand climate change over time. Sediments build up over geologic time in sedimentary basins, which are low areas in the Earth’s crust where material is...

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Column chromatography is used to separate lipid classes in a total lipid extract. A total lipid extract, or TLE, is often a complex mixture made up of hundreds or even thousands of compounds. Researchers may only need a few target compounds, so they remove the compounds they are not studying. Those target compounds can belong to different classes, including alkanes, ketones, alcohols, and acids. In some studies, a sample may contain many compounds, but only a small set matters for analysis.

removal of branched and cyclic compounds by urea adduction for uk'37 paleothermometry

removal-branched-cyclic-compounds-urea-adduction-for-uk-37

Urea Adduction Separates Lipid Shapes

Urea adduction separates straight-chain lipids from branched and cyclic compounds in a total lipid extract. Researchers use this step when they want only a small set of target molecules from a sample that may contain hundreds or even thousands of compounds. For paleothermometry, the target compounds are the alkenones used in U k'37 and the isoprenoidal glycerol dialkyl glycerol tetraethers, or GDGTs, used in MBT/CBT. Together, these organic paleothermometers depend on only six compounds: two...

earth science

This collection features topics ranging from geology to geochemistry; with a variety of demonstrations including physical and chemical properties of minerals and the analysis of rock formations. 

Learn how branched GDGTs in lake sediments are extracted, purified, and measured with LC-MS to reconstruct past temperature and climate records.

Sediment Biomarkers for Past Climate Records | JoVE K12

Pennsylvania State Academic Standards

Earth and Space Science

Human Sustainability

3.3.9-12.M

Louisiana Student Standards for Science

High School

Earth’s Systems

HS-ESS2-4

HS-ESS3-6

ohios-learning-standards-and-model-curriculum

Ohio’s Learning Standards and Model Curriculum

Physical Geology

Minerals

properties-minerals-hardness-luster-cleavage-streak-crystal-shape

Properties of minerals (hardness, luster, cleavage, streak, crystal shape, fluorescence, flammability, density/specific gravity, malleability)

Earth's History

The geologic rock record

Plate Tectonics

Historical review

Glacial Geology

Glaciers and glaciation

Virginia  Standards of Learning

HIgh School

ES.5

ES.5.a

ES.10

ES.10.d

Texas Essential Knowledge and Skills

Earth Systems Science

112.49.c.11

112.49.c.11.E.

Alabama Course of Study Science

9-12.ESS.2.5.d

9-12.ESS.2.6.a

Next Generation Science Standards

Earth’s Place in the Universe

HS-ESS1-6

Florida Department of Education

SC.912.E.7

SC.912.E.7.7

new-york-state-science-learning-standards

New York State Science Learning Standards

Physical Science

HS. Structure and Properties of Matter

HS-PS1-10.

HS. Waves and Electromagnetic Radiation

HS-PS4-5.

Life Science

matter-and-energy-in-organisms-and-ecosystems

Matter and Energy in Organisms and Ecosystems

HS-LS1-6.

HS-LS2-4.

Earth and Space Sciences

History of Earth

HS-ESS1-6.

HS-ESS2-6.

HS-ESS2-7.

Jeff Salacup

Overview

Principles of Branched Glycerol Dialkyl Glycerol Tetraether Biomarkers

Branched GDGT Extraction

Biomarker Purification and Analysis

Applications

Summary

Igneous Volcanic Rock

Source: Laboratory of Alan Lester - University of Colorado Boulder
Igneous rocks are the products of cooling and crystallization of magma. Volcanic rocks ...

The Carbon Cycle

Carbon is the basis of all organic matter on Earth, and is recycled through the ecosystem in two primary processes: one in which carbon is exchanged among ...

Igneous Intrusive Rock

Source: Laboratory of Alan Lester - University of Colorado Boulder
Igneous rocks are products of the cooling and crystallization of high temperature ...

Using Topographic Maps to Generate Topographic Profiles

Source: Laboratory of Alan Lester - University of Colorado Boulder
Topographic maps are &#34;plan-view&#34; representations of Earth&#39;s ...

Determining Spatial Orientation of Rock Layers with the Brunton Compass

Source: Laboratory of Alan Lester - University of Colorado Boulder
Most rock units exhibit some form of planar surfaces or linear features. Examples ...

Making a Geologic Cross Section

Source: Laboratory of Alan Lester - University of Colorado Boulder
Geologic maps were first made and utilized in Europe, in the mid-to-late 18th century. ...

Use models to explain how mantle convection powers plate tectonics.

ESS.EES.2.1

Analyze and interpret data to predict locations of volcanoes and earthquakes based on plate boundaries.

ESS.EES.2.2

An Overview of Alkenone Biomarker Analysis for Paleothermometry

Topographic Surveying and Contours

Topographic surveying is critical for documenting the Earth's surface, focusing on capturing elevations, slopes, and natural and man-made features. It is ...

Plotting of Topographic Maps

Topographic maps represent the Earth's surface features using contour lines, which connect points of equal elevation to create a two-dimensional ...

Methods of Obtaining Topography

Topography involves measuring and mapping land elevations, natural features, and artificial structures to create accurate representations of the terrain. ...

Use models to explain how plate tectonics influence topography.

ESS.EES.2.3

The Soil Ecosystem

Plants obtain inorganic minerals and water from the soil, which acts as a natural medium for land plants. The composition and quality of soil depend not ...

Conditions on Early Earth

What are Biogeochemical Cycles?

The most common elements in organic molecules, carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus, are only available in the ecosystem in limited ...

The Water Cycle

The Earth&rsquo;s hydrosphere includes all of the areas where the storage and movement of water occurs. Since water is the basis of all living processes, ...

The Nitrogen Cycle

Nitrogen atoms, present in all proteins and DNA, are recycled between abiotic and biotic components of the ecosystem. However, the primary form of ...

The Phosphorus Cycle

Unlike carbon, water, and nitrogen, phosphorus is not present in the atmosphere as a gas. Instead, most phosphorus in the ecosystem exists as compounds, ...

The Sulfur Cycle

Sulfur, an important element in the chemical makeup of proteins, is recycled through the atmosphere and aquatic and terrestrial environments. Found in the ...

Bioremediation

Bioremediation is the use of prokaryotes, fungi, or plants to remove pollutants from the environment. This process has been used to remove harmful toxins ...

Carry out investigations to explain how the rock cycle and rates of weathering, erosion, and soil formation influence Earth's systems.

ESS.EES.2.4

What is Climate?

Climate refers to the prevailing weather conditions in a specific area over an extended period. As the saying goes, &#8220;Climate is what you expect. ...

What is Weather?

Overview

Weather refers to the current state of atmospheric conditions at a specific time and place. Weather is temporary and is influenced by the ...

Variation of Atmospheric Pressure

Change in atmospheric pressure with height is particularly interesting. The decrease in atmospheric pressure with increasing altitude is due to the ...

/files/media/science-education/science-education-thumbs/14711.jpg

Analyze and interpret data to explain how volcanic activity influences changes in Earth's atmosphere, geosphere, biosphere, and hydrosphere.

ESS.EES.2.5

States of Water

Water exists in any one of the three classical states: solid (ice), liquid (water), and gas (steam or water vapor). The state of water depends on i) the ...

The potential of hydrogen (pH) is a measure of the acidity or basicity of a water-based solution determined by the concentration of hydronium ions (H3O+). ...

Solvents

A solvent is a substance, most often a liquid, that can dissolve other substances. Here, the substance being dissolved is called a solute. When a solvent ...

Redox Reactions

Oxidation-reduction or redox reactions involve the transfer of electrons from one molecule or atom to another. When an atom gains an electron, another ...

Carry out investigations to explain the properties of water.

ESS.EES.3.1

Analyze how the geosphere is shaped by plate tectonics and the rock cycle.

Sediment Biomarkers for Past Climate Records

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