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Page 4 November 12,2008 <br /> Cuttings were described on the basis of Munselr color[GSA, 1991.Geologic Society of America <br /> Rock Color Chart(using Munselle color chips)7 h Printing],rock type,and typical physical <br /> characteristics. Color in the log refers to the wet color of the examined chip(s). Numerous intervals <br /> produced very fine-grained material with little to no rock chips. When these cuttings were wet-sieved <br /> in an attempt to separate indurated cuttings from other material,they typically formed amorphous <br /> clayey balls. This material was described as mudstone or claystone. Where relatively hard singular <br /> chips were present,the rock type was typically described as a sandstone,siltstone,or shale. Shale was <br /> more commonly applied to cuttings that formed tabular chips. This is not to imply the material would <br /> have been fissile in outcrop. The term mudstone was also used to describe singular chips that were <br /> more blocky in appearance. <br /> The Brushy Basin in the borehole interval consisted of interbedded mudstone,shale,siltstone,and <br /> sandstone. A general description of the stratigraphy encountered is as follows: <br /> 0—25 ft: Yellow to gray brown to olive gray Mudstone with interbedded Siltstone and minor <br /> very fine-grained Sandstone:weak to well indurated;mild to moderate effervescence; <br /> no chips to chips I cm long. <br /> 25—30 ft: Pale yellow brown Sandstone:very-fine grained,well rounded,well sorted,non- <br /> cemented grains;no effervescence;no chips(loose unconsolidated material). Driller <br /> notes some damp cuttings at 30 ft. <br /> 30—45 ft: Yellow gray,yellow brown(variegated)Sandstone with Mudstone: Sandstone may be <br /> in form of weak to strongly indurated chips(minor);weak to no effervescence;few <br /> chips;Mudstone in form of balled clay. <br /> 45—55 ft: Yellow green,green gray to olive gray Shale:Very fined-grained(gritty)texture;well <br /> indurated angular chips;moderate effervescence;calcite vein observed. <br /> 55—70 ft: Yellow brown,olive green,moderate brown,light gray Mudstone(balled)+Shale <br /> (chips);weakly indurated;strong to no effervescence. <br /> 70—85 ft: Gray green,olive green Shale+Mudstone and Siltstone;Shale chips are<lmm to 1.5 <br /> cm;very fine-grained;well indurated;moderate effervescence;Mudstone in form of <br /> balled clay,not indurated(no chips);Damp at—78 ft. Produce water from borehole <br /> with air injection after 5 and 10 minute set times.Rig chatter at 80 to 85 ft. <br /> 85—110 ft: Gray green,brown gray,olive gray Shale+Siltstone:very fine-grained(silt minor <br /> sand grains);well indurated;moderate to strong effervescence;chips 1 min to 2 cm <br /> long;Rig chatter. <br /> 110—120 ft: Light olive gray Sandstone+— 10%as above:very fine-grained,rounded well sorted <br /> sand grains,minor opaque grains:some Fe staining;no induration(no chips); <br /> moderate effervescence. <br /> Groundwater at the monitoring well was associated with damp cuttings at a depth of approximately 78 <br /> ft while drilling. After well completion,the actual static water level was near 71 ft bgs. This interval is <br /> associated with a shale/mudstone unit that apparently exhibited some cementation as drill cuttings at <br /> this depth began to produce competent chips compared to clayey unconsolidated material above.Below <br /> this unit,at a depth of 80 ft,rig chatter became more prevalent,also indicating a more-competent unit. <br /> It is suspected that these competent beds may have a more brittle character allowing the secondary <br /> FFilas111208.doc <br />