Update: Rock Model Council Grove Group

Panoma Field, Southwest Kansas

Kansas Geological Survey

Hugoton Project

Martin K. Dubois Alan Byrnes

Core Descriptions Core Analysis

103514

6439

Core Analysis Data Set

Core Data Sources

Wells with LAS Files by Consortium Members

3900 Gross3200 Net Wells

Idealized Depositional Model

Major Lithofacies

Nonmarine Shaly Siltstone

Nonmarine Siltstone

Dolomite

Med – Coarse Grained Pkst-Grnst

V. Fine – Fine Grained Pkst-Grnst

Phylloid Algal Bafflestone

Mudstone – Wackestone

Silty Mudstone-Wkst

Marine Siltstone

Marine Shale

Lithofacies Distribution in Six Council Grove Cores

Council Grove Strat Column Formation Member Informal

Ma

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top

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A S

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f C

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Council Grove GroupStructure and Isopach Maps

Marine vs. Nonmarine (thickness)

Marine vs. Nonmarine (% total)

Mapped Intervals

Gross thickness from the top of Council Grove (A Shale) to the top of the Roca Shale (D Shale, base of Grenola, base of C Limestone)

1. Nonmarine Silstones and Sandstones2. Nonmarne Shaley Siltstones3. Marine Carbonates (“clean”, shallow)4. Marine Silica-rich Rocks (deeper)

These four major groups are fairly easily recognized with minimum electric log suites.

NonmarineSilt and Sand vs. Shale and Silt (thickness)

NM Sand (1-3), NM Silt (1-2) NM Shly Silt (1-0>1)

NonmarineSilt and Sand vs. Shale and Silt (% of total nonmarine)

NM Sand (1-3), NM Silt (1-2) NM Shly Silt (1-0>1)

Nonmarine Siltstones

MarineCarbonate vs. Silica-rich (thickness)

Pkst-Grnst (4>5-4>6-_ _1>9), Dol. (6>8), Baff-stone (_7), Mdst-Wkst (5-0>3)

Silty Mdst-Wkst (3>4-0>3), Mar. Shale, Silt, Sand (0,2-1>7)

MarineCarbonate vs. Silica rich (% of total marine)

Pkst-Grnst (4>5-4>6-_ _1>9), Dol. (6>8), Baff-stone (_7), Mdst-Wkst (5-0>3)

Silty Mdst-Wkst (3>4-0>3), Mar. Shale, Silt, Sand (0,2-1>7)

Med-Coarse Grained Packstone-Grainstone

Phylloid Algal Bafflestone

cm

Marine Carbonate Reservoir Lithofacies(Thickness and % of Marine Rocks)

Pkst-Grnst (4>5-4>6-_ _1>9), Dol. (6>8), Bafflestone (_7)

Conclusions

1. On a gross scale, major rock types show predictable distribution patterns throughout the Panoma Field.

2. Thinning in the marine rocks to the northwest is compensated by thickening in the nonmarine intervals. Overall thickness of the Council Grove is relatively consistent throughout Panoma.

3. The influx of quartz silt, very fine sand and clay from the west and northwest is quite dramatic, on a regional scale, and is evident in both the nonmarine and marine intervals.

4. Better marine carbonates reservoir rocks tend to be concentrated in the in the central and southeast portions of Panoma.

5. Conversely, better nonmarine reservoir rocks tend to be concentrated in the west and northwestern portion of the Panoma field