Presented by: Kathleen Neset

Wellsite Geology and Mudlogging

North Dakota Stratigraphic Column

Bakken Formation~360 Million Years OldPaleozoic EraMississippian/Devonian Period~110’ thick

Three Forks/Sanish~370 Million Years OldPaleozoic EraDevonian Period~240’ thick

Bakken

Three Forks

StratigraphyStratigraphy

Three Forks FormationThree Forks Formation

Bakken FormationBakken Formation

Lodgepole FormationLodgepole Formation

lower

middle

upper

Pelmatozoan limestone

“False Bakken”

Devon

ian

Mis

sis

sip

pia

n

“Sanish”

GR Res

Lithofacies 7 - SiltstoneLithofacies 7 - Siltstone

Lithofacies 4 – Interbedded Dark Grey Lithofacies 4 – Interbedded Dark Grey Shale and Buff Silty SandstoneShale and Buff Silty Sandstone

Lithofacies 3 - SandstoneLithofacies 3 - Sandstone

Lithofacies 2 – Interbedded Dark Grey ShaleLithofacies 2 – Interbedded Dark Grey Shale and Buff Silty Sandstoneand Buff Silty Sandstone

Lithofacies 1 - SiltstoneLithofacies 1 - Siltstone

(From LeFever and others, 1991)Lower Shale

Upper Shale

Lithofacies of the Middle Lithofacies of the Middle MemberMember

DrillpipeNon-magnetic Drill Collar

Bent Sub

Mud MotorRotating Sub

HS (0)

90R90L

45R45L

135R135L

180 (LS)

Upper SS

Gamma 60-80 API

ROP 30-60 ft/hr

Lithology Sandstone

MiddleStringer

Gamma 90-100+ API

ROP 50 ft/hr

Lithology Shale

Target

Gamma 30-50 API

ROP 70 ft/hr

Lithology Sandstone

Base Target

Gamma 60-90 API

ROP 25-40 ft/hr

Lithology Sandstone/Siltstone

Three Forks

Gamma 100+ API

ROP 20-30 ft/hr

Lithology Shale

ND Research – study in currently drilling wells to determine fracture stimulation growth – continued research frac methods.

Very early in learning Bakken/Sanish.

Bottineau County – Spearfish & Three Forks.

Request update study by USGS.

Widespread Bakken deposits

Phase I – initial drilling – define limits of pay

Phase II – development drilling – hold leases

Phase III – infill drilling – multipad drilling

Phase IV – secondary & tertiary recovery

Phase I

Phase III