SHALE HYDRAULIC FRACTURING DRILLING, CASING AND CEMENTING ...
EXPLORE SHALE DRILLING PAD
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An overview of the geology and terminology of natural gas development in the Marcellus Shale. EXPLORE SHALE What is the Marcellus Shale? The Marcellus Shale is a geologic formation that contains large amounts of natural gas in the cracks and pores of its rocks. It lies at varying depths from the surface to 9,000 feet and is believed to hold up to hundreds of trillions of cubic feet of natural gas. WITH SUPPORT FROM 50 Miles EXTENT OF MARCELLUS SHALE Why is the Marcellus Shale being developed now? Geologists have known that the Marcellus has been capable of producing relatively low volumes of natural gas for more than 50 years, but recent horizontal drilling advancements combined with hydraulic fracturing (“fracking”) techniques have made extracting gas more profitable. Drilling firms are now leasing thousands of acres of mineral rights in order to develop natural gas wells. Avg. depth of residential water wells 200 FEET Map & Cross Section Courtesy of Penn State Marcellus Center for Outreach and Research LEARN MORE AT EXPLORESHALE.ORG What is shale? Shale is a dense, low permeability sedimentary rock. Shale differs from similar rocks by often breaking along thin layers that are typically less than one centimeter in thickness. GEOLOGIC CROSS SECTION OF MARCELLUS SHALE 2. FRACTURING Fracking fluid is injected into the casing under high pressure and out of the perfs into the rock where it increases pressure underground, causes shale layers to crack, and creates pathways for natural gas within the shale to escape. 3. PRODUCTION After a section of a well is fractured, a plug is set in order to temporarily seal off the section. After the entire horizontal length of the well has been fractured, the plugs are removed, fracking fluids are allowed to flush out, and production of natural gas begins. Small holes are shot through the casing, cement, and a short distance into the shale. 1. PERFORATION Horizontal drilling is a process that sends a drill vertically underground, then turns it at a 90-degree angle and drills horizontally. On average, horizontal wells produce three to five times more natural gas than vertical ones. HORIZONTAL DRILLING Stages of Fracturing and Production Sources: Experts from Penn State, Bucknell, and Malcolm Pirnie (for details, see http://exploreshale.org) 1000 FEET 0 FEET 2000 FEET 3000 FEET 4000 FEET 5000 FEET AQUIFERS Aquifers are layers or zones where groundwater can be usefully extracted by drilling a water well. Aquifers are commonly found at depths between 20 and 250 feet, but may exceed 1000 feet. HYDRAULIC FRACTURING FLUID Fracking fluid is typically comprised of water, between five and ten additives, and proppants. The chemical additives are typically less than 1% of the composition of the fluid. The chemicals reduce friction, avert microorganism growth, and prevent corrosion of pipes. Proppants are porous materials such as sand or ceramic beads that hold open newly created shale fractures. Flowback Flowback is fluid that returns to the surface with extracted gas. It may contain clay, salts, rock particles, other naturally occurring elements, and trace concentrations of fracking chemicals. Flowback is captured and must be treated and reused at another drill site, or transported by truck or pipeline for proper disposal. WELL CASING Well casing is steel pipe that is inserted into a section of a drilled borehole and cemented in place. The cement is intended to seal the well, isolate the casing from groundwater, and prevent natural gas from leaking up around the outside of the pipe. DRILLING PAD
Transcript of EXPLORE SHALE DRILLING PAD
An overview of the geology and terminology of natural gas development in the Marcellus Shale.
EXPLORE SHALEWhat is the Marcellus Shale?The Marcellus Shale is a geologic formation that contains large amounts of natural gas in the cracks and pores of its rocks. It lies at varying depths from the surface to 9,000 feet and is believed to hold up to hundreds of trillions of cubic feet of natural gas.
WITH SUPPORT FROM
50 Miles
EXTENT OFMARCELLUS SHALE
Why is the Marcellus Shale being developed now?Geologists have known that the Marcellus has been capable of producing relatively low volumes of natural gas for more than 50 years, but recent horizontal drilling advancements combined with hydraulic fracturing (“fracking”) techniques have made extracting gas more profitable.
Drilling firms are now leasing thousands of acres of mineral rights in order to develop natural gas wells.
Avg. depth of residential water wells
200 FEET
Map & Cross Section Courtesy of Penn State Marcellus Center for Outreach and Research
LEARN MORE AT EXPLORESHALE.ORG
What is shale?Shale is a dense, low permeability sedimentary rock. Shale differs from similar rocks by often breaking along thin layers that are typically less than one centimeter in thickness.
GEOLOGIC CROSS SECTION OF MARCELLUS SHALE
2. FRACTURINGFracking fluid is injected into the casing under high pressure and out of the perfs into the rock where it increases pressure underground, causes shale layers to crack, and creates pathways for natural gas within the shale to escape.
3. PRODUCTIONAfter a section of a well is fractured, a plug is set in order to temporarily seal off the section. After the entire horizontal length of the well has been fractured, the plugs are removed, fracking fluids are allowed to flush out, and production of natural gas begins.
Small holes are shot through the casing, cement, and a short distance into the shale.
1. PERFORATIONHorizontal drilling is a process that sends a drill vertically underground, then turns it at a 90-degree angle and drills horizontally. On average, horizontal wells produce three to five times more natural gas than vertical ones.
HORIZONTAL DRILLING
Stages of Fracturing and Production
Sources: Experts from Penn State, Bucknell, and Malcolm Pirnie (for details, see http://exploreshale.org)
1000FEET
0FEET
2000FEET
3000FEET
4000FEET
5000FEET
AQUIFERSAquifers are layers or zones where groundwater can be usefully extracted by drilling a water well. Aquifers are commonly found at depths between 20 and 250 feet, but may exceed 1000 feet.
HYDRAULIC FRACTURING FLUID Fracking fluid is typically comprised of water, between five and ten additives, and proppants. The chemical additives are typically less than 1% of the composition of the fluid. The chemicals reduce friction, avert microorganism growth, and prevent corrosion of pipes. Proppants are porous materials such as sand or ceramic beads that hold open newly created shale fractures.
FlowbackFlowback is fluid that returns to the surface with extracted gas. It may contain clay, salts, rock particles, other naturally occurring elements, and trace concentrations of fracking chemicals. Flowback is captured and must be treated and reused at another drill site, or transported by truck or pipeline for proper disposal.
WELL CASINGWell casing is steel pipe that is inserted into a section of a drilled borehole and cemented in place. The cement is intended to seal the well, isolate the casing from groundwater, and prevent natural gas from leaking up around the outside of the pipe.
DRILLING PAD
