Cross-borehole analysis of velocity and density

Lines, Larry; Tan, Henry; Schultz, A.

doi:10.1016/0016-7142(91)90033-9

Cited by 1 publication

(1 citation statement)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These benefits have led to gravity surveys being used in a number of environments to detect features of interest [ 3 ], including below the surface in boreholes. Borehole gravity sensing is used for a number of applications, including: remote sensing of gas and oil zones behind casing [ 4 ]; vertical density profiling for gravity map interpretation and for seismic modelling and analysis [ 5 ]; detection of geologic structures [ 6 , 7 ]; determination of reservoir porosity for reserve estimates [ 8 ]; monitoring of reservoir fluid conditions for production evaluation, and rock-type change mapping for groundwater and engineering studies [ 9 , 10 ]; Carbon Capture and Storage (CCS) monitoring [ 11 , 12 ]; as well as tests of fundamental physics [ 13 , 14 ].…”

Section: Introductionmentioning

confidence: 99%

Magneto-optical trapping in a near-suface borehole

et al. 2023

View full text Add to dashboard Cite

Borehole gravity sensing can be used in a number of applications to measure features around a well, including rock-type change mapping and determination of reservoir porosity. Quantum technology gravity sensors, based on atom interferometry, have the ability to offer increased survey speeds and reduced need for calibration. While surface sensors have been demonstrated in real world environments, significant improvements in robustness and reductions to radial size, weight, and power consumption are required for such devices to be deployed in boreholes. To realise the first step towards the deployment of cold atom-based sensors down boreholes, we demonstrate a borehole-deployable magneto-optical trap, the core package of many cold atom-based systems. The enclosure containing the magneto-optical trap itself had an outer radius of (60 ± 0.1) mm at its widest point and a length of (890 ± 5) mm. This system was used to generate atom clouds at 1 m intervals in a 14 cm wide, 50 m deep borehole, to simulate how in-borehole gravity surveys are performed. During the survey, the system generated, on average, clouds of (3.0 ± 0.1) × 105 87Rb atoms with the standard deviation in atom number across the survey observed to be as low as 8.9 × 104.

show abstract