Potential for deep basin-centered gas accumulation in Hanna Basin, Wyoming

Deep basin gas, which is trapped deep in a basin, is a kind of unconventional natural gas. It is also one of the important unconventional gas resources. In the previous studies of the mechanism of deep basin gas accumulation, force balance and material balance are considered as essential conditions for the formation of deep basin gas reservoirs. However, the gravity of natural gas is not fully taken into account in the analysis of force balance. In this dissertation, the density of natural gas under the condition of underground temperature and pressure is calculated by using the EOS. The result shows that the density of natural gas cannot be neglected and the PR EOS is applicable to the analysis of the relationship between the volume of natural gas and the condition of underground temperature and pressure.

Download Full-text

The Genetic Mechanism and Model of Deep-Basin Gas Accumulation and Methods for Predicting the Favorable Areas

Acta Geologica Sinica - English Edition ◽

10.1111/j.1755-6724.2003.tb00135.x ◽

2010 ◽

Vol 77 (4) ◽

pp. 547-556 ◽

Cited By ~ 4

Author(s):

WANG Tao ◽

PANG Xiongqi ◽

MA Xinhua ◽

JIN Zhijun ◽

JIANG Zhenxue

Keyword(s):

Genetic Mechanism ◽

Deep Basin ◽

Gas Accumulation

Download Full-text

DEEP BASIN GAS: A NEW EXPLORATION PARADIGM IN THE NAPPAMERRI TROUGH, COOPER BASIN, SOUTH AUSTRALIA

The APPEA Journal ◽

10.1071/aj00009 ◽

2001 ◽

Vol 41 (1) ◽

pp. 185 ◽

Cited By ~ 12

Author(s):

R.R. Hillis ◽

J.G.G. Morton ◽

D.S. Warner ◽

R.K. Penney

Keyword(s):

South Australia ◽

Source Rocks ◽

Deep Basin ◽

Gas Accumulation ◽

Impermeable Barrier ◽

Trapped Gas ◽

Giant Fields ◽

Rock Section ◽

Sweet Spots ◽

Cooper Basin

Deep basin hydrocarbon accumulations have been widely recognised in North America and include the giant fields of Elmworth and Hoadley in the Western Canadian Basin. Deep basin accumulations are unconventional, being located downdip of water-saturated rocks, with no obvious impermeable barrier separating them. Gas accumulations in the Nappamerri Trough, Cooper Basin, exhibit several characteristics consistent with North American deep basin accumulations. Log evaluation suggests thick gas columns and tests have recovered only gas and no water. The resistivity of the entire rock section exceeds 20 Ωm over large intervals, and, as in known deep basin accumulations, the entire rock section may contain gas. Gas in the Nappamerri Trough is located within overpressured compartments which witness the hydraulic isolation necessary for gas saturation outside conventional closure. Furthermore, the Nappamerri Trough, like known deep basin accumulations, has extensive, coal-rich source rocks capable of generating enormous hydrocarbon volumes. The above evidence for a deep basin-type gas accumulation in the Nappamerri Trough is necessarily circumstantial, and the existence of a deep gas accumulation can only be proven unequivocally by drilling wells outside conventional closure.Exploration for deep basin-type accumulations should focus on depositional-structural-diagenetic sweet spots (DSDS), irrespective of conventional closure. This is of particular significance for a potential Nappamerri Trough deep basin accumulation because depositional models suggest that the best net/gross may be in structural lows, inherited from syndepositional lows, that host stacked channel sands within channel belt systems. Limiting exploration to conventionally-trapped gas may preclude intersection with such sweet spots.

Download Full-text

Reservoir characterisation of the Patchawarra Formation within a deep, basin-margin gas accumulation

The APPEA Journal ◽

10.1071/aj13009 ◽

2014 ◽

Vol 54 (1) ◽

pp. 45 ◽

Cited By ~ 1

Author(s):

Tim Stephens ◽

Brenton Richards ◽

Joseph Lim

Keyword(s):

Gas Flows ◽

Deep Basin ◽

Gas Accumulation ◽

Reservoir Architecture ◽

Trap Potential ◽

Gas Fields ◽

Depositional Setting ◽

The Impact ◽

Basin Margin ◽

Cooper Basin

An exploration program to assess the basin-centred gas (BCG) and stratigraphic trap potential of the Mettika Embayment in the southern Cooper Basin resulted in the discovery of gas at Hornet–1 and Kingston Rule–1. The embayment is a confined fluvial sedimentary depocentre surrounded by prolific gas fields producing from structurally closed anticlines. Gas pay was identified and both wells produced sustained gas flows to surface of between 1.2 and 2.2 MMscf/d after fracture stimulation. Core collected from the Patchawarra Formation sandstone reservoir was analysed to constrain the depositional environment and establish petrophysical properties by routine and special core analysis. An integrated reservoir study was undertaken to understand depositional setting, reservoir architecture, trapping mechanisms, permeability, and saturation controls on productivity. Gas identified in the embayment appears to have accumulated in subtle stratigraphic and combination structural traps against the flanks of existing fields and does not display the geological and physical characteristics of a BCG play. The impact and analysis of hydrocarbon migration and reservoir trapping influences in this basin-margin gas accumulation may be applicable to other under-explored flank and trough plays of the Cooper Basin.

Download Full-text