Cave facies 1 - Undisturbed strata facies

Void

Cave facies 3 - Highly disturbed strata facies

Cave facies 4 - Coarse-clast chaotic breccia facies

Cave facies 2 - Disturbed strata facies

IW–1N

IW–2N

IW–3N

IW–4N

Avon Park

permeable zone

Top of glauconite

marker

Uppermost permeable zone of the Lower Floridan aquifer

Boulder

Zone

Avon Park Formation

sequence 1

Upper Floridan

aquifer

Intermediate

confining unit

Middle

confining unit 1

Middle

confining unit 2

Confining unit 

within the 

Lower

Floridan

aquifer

Base of brackish 

water zone

Avon Park Formation

sequence 2

base not delineated

Lower Arcadia

Formation

Upper Avon

Park

Formation

Upper-Middle

Avon Park

Formation

Lower Middle

Avon Park

Formation

Lower

Avon Park

Formation

Oldsmar

Formation

1,800

1,900

2,000

2,100

2,200

2,300

2,400

2,500

2,600

2,700

2,800

2,900

3,000

3,100

3,200

700

800

900

1,000

1,100

1,200

1,300

1,400

1,500

1,600

1,700

3,300

SOUTH EAST WEST

Depth below land surface, in feetDepth below land surface, in feet

A

A'

Set 24-in.

casing

to 2,780 ft.

Set 

24-in.

casing

to 

2,940 ft.

Upper Arcadia

Formation

Stock Island

Formation

Stock Island

Formation

Upper Arcadia

Formation

Lower Arcadia

Formation

1,800

1,900

2,000

2,100

2,200

2,300

2,400

2,500

2,600

2,700

2,800

2,900

3,000

3,100

3,200

Set 24-in.

casing

to 2,620 ft.

700

800

900

1,000

1,100

1,200

1,300

1,400

1,500

1,600

1,700

3,300

Set 24-in.

casing

to 2,970 ft.

X caliper

10 Inches 30

Y caliper

10 Inches 30

MD–IW–4N

422 ft 421 ft 513 ft

X caliper

10 Inches 30

Y caliper

10 Inches 30

X caliper

20 Inches 60

Y caliper

20 Inches 60 240 40

Natural gamma

0

50

API

Natural gamma

0

100

API

MD–IW–3N

240 40

Natural gamma

0 API 100

X caliper

10 Inches 80

Y caliper

10 Inches 80

Natural gamma

0 API 100 240 40

MD–IW–2N

NORTH

A A'

MD–IW–1N

Natural gamma

0 API 100

Sonic DT, in μsec/ft

240 40

X caliper

10 Inches 30

Y caliper

10 Inches 30

(MD–FA–1N)(MD–FA–2N)(MD–FA–3N)(MD–FA–4N)

Top of SS1

Top of SS2 Top of SS2

Top of SS1

Top of SS3

Top of SS4

Top of SS3

Top of SS4

Sonic DT, in μsec/ft Sonic DT, in μsec/ft Sonic DT, in μsec/ft

μsec/ft

Conceptualized limit to collapse structure

Conceptual limit to collapse structure

Video borehole wall image. 

Cave facies 1

Video borehole wall image. 

Cave facies 2

Video borehole wall image. 

Cave facies 4

Video borehole wall image. 

Cave facies 4

Video borehole wall image. 

Cave facies 3

Video borehole wall image. 

Cave facies 2

Video borehole wall image. 

Cave facies 2

Zone of coalesced 

collapsed-paleocave system

Video borehole wall image. 

Cave facies 2

Video borehole wall image. 

Cave facies 2

Video borehole wall image. 

Cave facies 2

Video borehole wall image. 

Cave facies 3

Video borehole wall image. 

Cave facies 1

In gauge borehole diameter and no vugs

In gauge borehole diameter and minor vugs

In gauge borehole diameter and vuggy

In gauge borehole diameter and very vuggy

Vugs along bedding plane

EXPLANATION

Borehole wall not described from borehole well video

Observations from borehole wall video

Cased section

Open section, monitored zone

Lithologic Units

Seismic Sequence Upper Boundaries

Hydrologic Units

Monitor Well

Injection Well

Bottom of 24-inch steel casing

Top of upper Arcadia Formation

Top of lower Arcadia Formation 

Top of upper Avon Park Formation

Top of upper-middle Avon Park Formation

Seismic Sequence 1 (SS1)

Depositional Sequence Upper Boundaries

Abbreviations

Top of Avon Park Formation sequence 2 

 (Reese and Cunningham, 2014)

inch

foot

microsecond per foot

American Petroleum Institute

Sonic interval transit time or delta t (compensated)

Top of Avon Park Formation sequence 1 

 (Reese and Cunningham, 2014)

Seismic Sequence 2 (SS2)

Seismic Sequence 3 (SS3)

Seismic Sequence 4 (SS4)

Top of lower-middle Avon Park 

 Formation

Top of lower Avon Park Formation

Natural gamma ray stratigraphic marker within lower 

 Avon Park Formation and Oldsmar Formation

Top of of glauconite marker as reported in Reese and 

 Cunningham (2014) and top of Oldsmar Formation

Upper Floridan aquifer

Geophysical Log Marker

Unnamed geophysical log marker

Avon Park permeable zone

Base of brackish water zone

Uppermost permeable zone of the 

 Lower Floridan aquifer

Boulder Zone

in.

ft

API

DT

Fractures

Ophiomorpha?

Prepared in cooperation with the 

Miami-Dade County Water and Sewer Department

U.S. Department of the Interior

U.S. Geological Survey

Scientific Investigations Report 2015–5013

Plate 2 of 2

Hydrologic, Lithostratigraphic, Seismic Sequence, and Depositional Sequence Section Through North District “Boulder Zone” Well Field, Miami-Dade County, Florida

By

Kevin J. Cunningham

2015

North District “Boulder Zone” Well Field Injection and Monitoring Wells

Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not 

imply endorsement by the U.S. Government

This map was printed on an electronic plotter directly from digital files. Dimensional calibration may vary 

between electronic plotters and between X and Y directions on the same plotter, and paper may change 

size due to atmospheric conditions; therefore, scale and proportions may not be true on plots of this map.

For sale by U.S. Geological Survey, Information Services, Box 25286, Federal Center, Denver, CO 80225, 

1–888–ASK–USGS

Digital files available at http://dx.doi.org/10.3133/sir20155013

Suggested Citation: Cunningham, K.J., 2015, Seismic-sequence stratigraphy and geologic structure 

of the Floridan aquifer system near “Boulder Zone” deep wells in Miami-Dade County, Florida: 

U.S. Geological Survey Scientific Investigations Report 2015–5013, http://dx.doi.org/10.3133/sir20155013.

ISSN 2328-0328 (online)