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Reconstructing Alluvial and Lacustrine Sedimentary Environments – Methods and Examples

Faith Fitzpatrick (fafitzpa@usgs.gov)

USACE sediment records workshop Aug 2010

Jim Knox photo, Halfway Creek Marsh

Halfway Creek mouth

and wetland

Black River delta

Lake Onalaska

Sedimentary features of interest • Texture

• Thickness

• Sorting

• Spatial extent and direction, in relation to flowing water

• Dipping or horizontal layering?

• Sequencing of layers

• Contact between deposits – gradual or sharp, eroded

• Density/compactness

• Biological matter – vegetation, shells, wood, roots

• Post-depositional structural features – cracks

• Soil development

Boardman River, Keystone Impoundment, Stop 1

(Graham’s List):

• Packing

• Lithology

• Size

• Shape

• Fabric

• Structure

Halfway Creek Post-Settlement Alluvial Changes

GOALS

• Describe the extent and character of historical sedimentation in the marsh

• Describe how recent sediment deposition compares to past times

• Give historical context to ongoing sediment load measurements

• Give evidence if sediment traps are making a difference

SETTING

Upper Mississippi River tributary near La Crosse, Wis.

Mouth part of the Upper Mississippi River Wildlife and Fish Refuge (USFWS)

EPA funded research for experimental wetlands and nutrient reductions

(Fitzpatrick et al., 2009)

(1) Reconnaissance of the area

• helicopter, canoe trip, drive-by, drone

• go with someone that knows the area

• Get a feel for the geomorphic setting of entire watershed

• Look for human footprint

(2) Review old and new regional and local maps

• Topography, soils, plat maps (old bridges/roads, railroads, towns, dams etc.)

• Get familiar with the glacial/post glacial history

• Get down to soil series descriptions for parent material origins, terrace development, etc.

• Old USACE maps (Warren surveys)

La Crosse County 1978 Plat

Evans, T.J., 2003, Geology of La Crosse

County, Wisconsin: Wisconsin

Geological and Natural History Survey

Bulletin 101, 33 p.

Halfway Creek geologic setting

(3) Compile Euro-American settlement history

• internet, local historical societies, and museums, libraries

• interview long-time residents and landowners

• State dam safety files

• log drives, dams, impoundments, channel alterations, levees

• Channel planform at section line crossings very accurate, not so between the section lines

• Looking for fording potential -- stream width and overall swiftness of the flow, substrate

• Riparian vegetation

• Presence of channels

• Meanders on larger streams

• First People trails and villages

Public land survey records

• Historical county atlases

Rainfall records

Floods and flood damages

Land use

Roads

Levees

Dams

• Historical aerial photos

Rainfall records

Floods and flood damages

Land use

Roads

Levees

Dams

Pre-settlement (1860) surface 5.6 ft

Levee breaks

Holmen dam

and millpond

Erosion/scour

from dam

failure

1938

Sept 2005

Late 1800s 2006

2006

Late 1800s

Holmen Dam, Halfway Creek, 1860-1957

Holmen, June 11,

1899

Halfway Creek levee/dike building 1919 (from dam files)

Summary of Halfway Creek historical events

1846

1906

1937-38

1973

2005

Halfway channel change 1846-2005

railroad and flood control

(5) Compile modern flow and sediment data

• Flow and flood recurrence intervals

• Sediment loads

• Any other data pertaining to study such as sediment chemistry or previous sedimentation studies

Jim Knox photo, Peter Hughes at Halfway Creek gage

Detailed Field Study

• Use geomorphic setting to guide locations for detailed work

• Transects based transverse and longitudinal to general flow patterns

• Coring done along transects

• Survey core locations and topography along transects

Types of Coring – Exploratory coring with Oakfield soil probe

1” diam. Sampling tube

Collects 12” core

Depth only limited by water table or filling hole

Deepest hole 15-20 ft

Field descriptions

Small samples

Clay to fine gravel

Sometimes works with dep. bars

photos by M. Peppler

Types of Coring – Hydraulic driven geoprobe

Variety of sampling tube lengths and styles

Discrete and open barrel

Swedish tapper for resistant gravel, weathered bedrock

Depths to about 100 ft.

Inner sleeve for archiving samples

4WD Mule mounted is especially versatile in rough terrain, also over ice for coring impoundments and shallow lakes

Most favorite

Types of Coring -Vibracoring

3” diam. Sampling tube

Driven by vibration

Traditionally Al irrigation pipe in 10’+ lengths but new materials

Older versions had to take cores back to the lab to cut.

Prone to rodding

My personal least favorite

Vibracoring floodplains of lower Fish Creek, WI

Types of Coring – Piston style

3” diam. Sampling tube

Hand push

Over ice or in a boat

Longest sampled interval was about 6 ft

Used by WI DNR for contaminants program sampling

Also valve-style models that work under same principal

Modified Livingston corer can take multiple depths

Types of Coring – Gravity corer/Box corers

Drives into sediment by gravity/weight of sampler

Used in deep water settings

Box corer provides ample sample for multiple lab chemical analyses.

USGS TX water science center, Pete VanMeter and Barbara Mahler

http://www.cee.mtu.edu/great_lakes/images2/spotlight_sediments.html

Any type of coring, land or sea… Measure penetration depth and length of recovery!

Much of what we do is driven by bulk density – conversion of volume to mass

Core shortening can happen multiple ways on land or under water:

Rodding

Preferential retrieval

Compaction (even inundated sites)

Loss of core upon retrieval

Make a note of what you think happened

ALWAYS measure penetration depth

ALWAYS measure length of recovery

Coring fluvial deposits requires multiple types of corers

Success of retrieving a good core depends on:

Thickness and extent of sand units (More is less)

Multiple units of varying texture and density (More is more)

Depth to the water table

Get a feel for how the different corers work in different conditions

Collect duplicate cores from same point to account for sampling variability (treat coring and subsampling like you would any lab chemistry quality assurance and control

EPA world--There are some QAPPs out there for coring for sediment chemistry if you need examples

Describing exposures, pits Same descriptive process as cores – easier to see structure

Cranberry River floodplain cores and exposures, Fitzpatrick et al., 2013

Modern

channel

Describing exposures, pits

Arvada Formation in a road cut near Arvada, CO (Leopold and Miller, 1954)

Modern

channel

Core locations and cross sections

Cross section

Core location

Pre-dam channel

Example of piston coring Neopit Millpond, Menominee Reservation, WI (Fitzpatrick and Peppler, 2003)

Example of piston coring Neopit Millpond, Menominee Reservation, WI, 2001

Setting up the piston core for a sample (photo by Barb Lensch, NRCS)

Example of coring Neopit Millpond, Menominee Reservation, WI

Lifting the corer and plugging the bottom (photo by Barb Lensch, NRCS)

Example of coring Neopit Millpond, Menominee Reservation, WI

Extruding a core vertically for subsampling (photo by Barb Lensch, NRCS)

Extruding a core horizontally for logging

Example of coring Neopit Millpond, Menominee Reservation, WI

Subsampling and vertical extrusion (photo by Barb Lensch, NRCS)

Example of coring Neopit Millpond, Menominee Reservation, WI

Placing interval into jar for trace elements analysis (photo by Barb Lensch, NRCS)

Example of coring Neopit Millpond, Menominee Reservation, WI

Logging (describing) a 2nd side-by-side core (photo by Barb Lensch, NRCS)

Example of coring, Neopit Millpond, Menominee Reservation, WI

Geoprobe core through impounded sediment to pre-dam peat (photo by Barb Lensch, NRCS)

Impounded sediment

Example of coring, Neopit Millpond, Menominee Reservation, WI

Piston core through impounded sediment to pre-dam peat (photo by Barb Lensch, NRCS) – Based on the historical maps, we knew in advance that we’d hit old floodplain

Impounded sediment

Types of Surveying Instruments Use what is appropriate for the field problem

Rod and hand level

Total station

Survey-grade GPS

....stitch with 1- to 3-m LiDAR

Describing cores

Describing cores

Photos Bill Richardson

FWS-21

Field logs of FWS-21

Lab descriptions of FWS-21

Elevation 652.7 ft

Geophysical tests – surface methods (Walker and Cohen, 2007 contains nice summary)

• Seismic reflection surveys

• Seismic refraction surveys

• Magnetometry (MAG)

• Ground penetrating radar (GPR)

• Electomagnetic Induction (EM)

• Electrical Resistivity Surveys (ER)

(Cohen, 2003, p. 186)

Geophysical tests – downhole methods (Walker and Cohen, 2007)

• Natural gamma logging

• EM Induction Logging

• Caliper Logging

• Temperature Logging

• Electomagnetic Induction (EM)

• Electrical Resistivity Surveys (ER)

Geophysical tests – logging techniques (Walker and Cohen, 2007)

• Electrical Resistivity (ER)

• Self-Potential (SP)

• Electro-magnetic (EM)

• Radioactive Gamm (natural gamma)

• Gamma-gamma (formation density logs)

• Neutron

• Thermal

• Elastic-wave propagation

• Elastic-wave propagation

• Gravimetric

• Caliper

• Magnetic

• SP-spontaneous potential

Connecting the dots

(7) Constructing stratigraphic diagrams

(Bridge, 2003)

Back to Halfway Creek example

(Fitzpatrick et al, 2009)

(Fitzpatrick et al, 2009)

1886-2006

1993-2006

Halfway Cr

(Fitzpatrick et al, 2009)

FWS-21

FWS-18

Linear overbank sedimentation rate (cm/yr)

Time period FWS-21 FWS 18 FWS-5

1860-1963 1.31 0.31

1963-2005 0.89 2.59

1886-2005 0.67

FWS-5

FWS-18

FWS-21

1860

surface

1860

surface

(Fitzpatrick et al, 2009)

Halfway Creek overbank sedimentation rates

(Fitzpatrick et al, 2009)

Halfway Creek overbank sedimentation rates

(Fitzpatrick et al, 2009)

188

187

186

185

184

183

182

181

100 200 300

North South

DISTANCE ACROSS VALLEY ( METERS)

Modern

channel

1906

channel

Distributary

channel of

North Fish

Water table

0

Organic-rich silty clay

Lacustrine- modified glacial till

Organic-rich silt loam

Red silt

Organic-rich silt

C. sand

AP

PR

OX

IMA

TE

ALT

ITU

DE

(

ME

TE

RS

)

Pre-settlement

surface

North Fish Creek Lower main stem—partial valley cross section

Location

(Fitzpatrick, 1998)

(Fitzpatrick, 1998)

Wolf River, WI

(Fitzpatrick 2005)

700

800

900

1000

1100

1200

1300

0 5 10 15 20 25 30 35 40 45RIVER MILE ABOVE SHAWANO DAM

AL

TIT

UD

E (

FE

ET

)

Shawano Dam

Balsam Row Dam

Keshena Falls

Langlade/Menominee County Line

Study reach

T2

T9 T7

(Fitzpatrick, 2005)

Wolf River longitudinal profile

Transect 2 Wolf River impoundment

(Fitzpatrick, 2005)

Wolf River Impoundment, Transect 2, Core 1

0

1

2

3

4

5

6

7

80 4 8

ACTIVITY

(PICOCURIES PER LITER)

DE

PT

H (

FE

ET

)

Cs137 profile

1963

~1954

1927

1999 0

1

2

3

4

5

6

7

8

0 50 100PERCENT

DE

PT

H,

IN F

EE

T

Sand Silt Clay

Keshena

Dam Failure? Linear sedimentation: 1927-63:1.21 in/yr 1963-99: 0.88 in/yr Mass sedimentation: 1927-63: 1.04 lb/ft2/yr 1963-99: 1.11 lb/ft2/yr

Particle size

(Fitzpatrick, 2005)

Wolf River impoundment

Transect 7 Wolf River – 4.5 mi upstream of dam

(Fitzpatrick, 2005)

Transect 9

Q2

Q25

Wolf River near Keshena

(Fitzpatrick, 2005)

790

795

800

805

810

815

820

825

830

835

840

0

2000

4000

6000

8000

1000

0

1200

0

1400

0

1600

0

1800

0

2000

0

2200

0

2400

0

2600

0

2800

0

3000

0

3200

0

3400

0

3600

0

3800

0

STREAM DISTANCE, IN FEET

EL

EV

AT

ION

, IN

FE

ET

(N

GV

D)

Wolf River Longitudinal Profile with post-dam sedimentation

Balsam

Row Dam

1999 bed profile

Pre-dam profile

Keshena Falls

Flow T7 T9

T2

(Fitzpatrick, 2005)

Laboratory Analysis

• Particle size

• Traditional sieving

• Laser scattering

• Bulk density

• Water weight percent, water content, porosity

• Organic content (LOI), total organic carbon

• LOI determined by weight loss after ashing or ignition at 550o for 1 hour (Dean, 1974)

• Chemistry

• Trace elements

• Nutrients

• Macrofossils, including pollen

• Age determinations

• – radioisotopes (Thursday presentation)

• Optical luminscence

• Freeze-drying samples are a nice alternative for archiving and splitting

[Overall, technology is moving away from laboratory analysis into in situ portable analyzers]

Particle size classes vary by agency/tradition

Note: USDA soils analysis usually use 0.075 mm as break between silt and sand; USGS and more water related studies tend to use 0.063 mm.

Sometimes clay is set to 0.004 or 0.002

(Schaetzl and Anderson, 2005)

Laser-scattering, portable particle size analyzer

The LISST is a portable particle size analyzer that determines particle size distribution and particle volume concentration. The LISST is a laser-scattering, battery powered portable bench-top particle analyzer developed for use in the field or in the laboratory. Using the same small-angle laser scattering principles as other LISST products, the LISST-Portable analyzes samples in a wet-state and obtains particle size distribution and particle volume concentration. A unique feature of the LISST-Portable is the mixing chamber that incorporates a stirring capability to keep large particles suspended. Also, the chamber is equipped with in/out flow-through valves that can be used for circulating samples drawn during online process.

Mean grain size – digital imaging (David Rubin, USGS, 2010 FISC abstract)

• USGS testing analyzer on sand-sized bed sediment in the Colorado River, Grand Canyon, following controlled releases from Glen Canyon dam

Bulk density

• Very common to use estimated dry bulk densities for mass calculations but measuring water weight percent and organic content (LOI).

• Rarely is ASTM standard method 854-92 used to determine specific gravity of material

• Sometimes direct dry weight/volume measurements are used.

Bulk density

• (W. Fitzpatrick 1993)

Ranges in specific weight used by the SCS for general design purposes (Chow, 1964, Handbook of applied hydrology)

Grain size Permanently submerged

(lb/ft^3) Aerated lb/ft3

Clay 40-60 60-80

Silt 55-75 75-85

Clay-silt mixtures 40-65 65-85

Sand-silt mixtures 75-95 95-110

Clay-silt-sand mixtures 50-80 80-100

Sand 85-100 85-100

Gravel 85-125 85-125

Poorly sorted sand and gravel

95-130 95-130

Bulk density estimated by water weight and LOI

= (D(2.5Ix + 1.6Cx )) / (D + (1-D) (2.5Ix + 1.6Cx)) Where: is dry bulk density (g cm-3), x is depth in the core, D is the proportion dry weight of unit wet volume, I is inorganic proportion of dry material (assuming a specific gravity of 2.45 g cm-3), C is organic proportion of dry material (assuming a specific gravity of 1.6 g cm-3). Quartz has a specific gravity of 2.65 g cm-3

(see Fitzpatrick et al, 2003 WRIR 02-4225 for summary)

= (22.2*(2.5*(86.5)+1.6*(13.5))) / (22.2+(77.8)*(2.5*(86.5)+1.6*(13.5))) Example for a lake sediment sample (high water content) (W) Water weight percent = 77.8 (D) Dry weight percent = 100-77.8 = 22.2 (C) Organic content percent = 13.5 (I) Inorganic content percent = 100 – 13.5 = 86.5 Bulk density = 0.285 g cm-3

Sediment Chemistry

• Constituents are assumed immobile under all conditions (present and past) to construct profiles and interpret past conditions

• Usually 1-2 cores represent a very large area

• Need quality assurance sampling

Assumptions • No erosion

• No chemical or physical remobilization

• No degradation over time (unless radiosotope)

• No bioturbation

• No pedogenesis

• No decomposition

• No diagenesis

What happens to nutrient-rich sediment deposited in a shallow lake?

Lac Courte Oreilles, WI; Fitzpatrick et al., 2003; Garrison and Fitzgerald, 2005)

Musky Bay

NE Bay

LCO-1

MB-1

Lac Courte Oreilles, NW WI; Fitzpatrick et al., 2003

Total Organic carbon Nitrogen Phosphorus Sulfur

Trends in nutrient concentrations in sediment profiles do not represent changes in nutrient concentrations in the lake over time (Sharon Fitzgerald’s work on the study)

Musky Bay Core, Lac Courte Oreilles, NW WI; Fitzpatrick et al., 2003)

OC:N N:P OC:P

Increasing ratios with depth indicate preferential recycling and loss of P with respect to both OC and N and preferential recycling of N with respect to OC. Gradual down-core increases in profiles reflect decomposition of organic matter. If there was a sudden increase in nutrient inputs, there should a sharp change in the curve.

Musky Bay Core, Lac Courte Oreilles, NW WI; Fitzpatrick et al., 2003)

OC:N

N:P OC:P

Normalizing N and P to Al and LOI. Al is used as a proxy to represent the mineral portion of the sediment. These core profiles also show smooth decreasing curves with depth, pointing toward organic matter decomposition and biological recycling of N and P over the upper 20 cm. (Sharon Fitzgerald’s work on the study)

Musky Bay Core, Lac Courte Oreilles, NW WI; Fitzpatrick et al., 2003; Garrison and Fitzgerald, 2005)

OC:N N:P OC:P

Representative trace elements, expect to be somewhat stable downcore. Al – proxy for mineral content of sediment Ca – may be used in cranberry operations to adjust pH Pb – airborne, human source from traffic, assume peak in 1976

Trace elements

Musky Bay Core, Lac Courte Oreilles, NW WI; Fitzpatrick et al., 2003; Garrison and Fitzgerald, 2005)

OC:N N:P OC:P

Biogenic silica concentrations in Musky Bay – upward increase over time indicating increasing eutrophication from cranberry farming or shoreland development ~1970 peak from what? The core did not reach pre-settlement deposits (Sharon Fitzgerald’s work on the study)

Biogenic silica

Human disturbance

Musky Bay Core, Lac Courte Oreilles, NW WI; Fitzpatrick et al., 2003)

N:P OC:P

Fragilaria capucina increased dramatically after the mid 1990s and is indicative of floating algal mat. Analyses done by Paul Garrison at the WI DNR.

Diatoms in core MB-1

Questions on Methods and Examples?