scholarly journals Strain Hardening in Salt—Results of the SALMON Experiment

1990 ◽  
Vol 112 (2) ◽  
pp. 145-148 ◽  
Author(s):  
L. A. Glenn

SALMON was a nuclear explosion in the Tatum salt dome, near Hattiesburg, Mississippi, that took place on October 22, 1964. Computational attempts to simulate the experimental results had been largely unsuccessful. Recent calculations suggest that the reason is that the salt yield strength is extremely sensitive to strain hardening. The hardening effect had not been observed in laboratory-scale measurements, which were not made at small enough strain levels and may not have been representative of in-situ pore-fluid pressure.

Geophysics ◽  
2017 ◽  
Vol 82 (5) ◽  
pp. D319-D326 ◽  
Author(s):  
Pierpaolo Marchesini ◽  
Jonathan B. Ajo-Franklin ◽  
Thomas M. Daley

The ability to characterize time-varying reservoir properties, such as the state of stress, has fundamental implications in subsurface engineering, relevant to geologic sequestration of [Formula: see text]. Stress variation, here in the form of changes in pore fluid pressure, is one factor known to affect seismic velocity. Induced variations in velocity have been used in seismic studies to determine and monitor changes in the stress state. Previous studies conducted to determine velocity-stress sensitivity at reservoir conditions rely primarily on laboratory measurements of core samples or theoretical relationships. We have developed a novel field-scale experiment designed to study the in situ relationship between pore-fluid pressure and seismic velocity using a crosswell continuous active-source seismic monitoring (CASSM) system. At the Cranfield, Mississippi, [Formula: see text] sequestration field site, we actively monitored seismic response for five days with a temporal resolution of 5 min; the target was a 26 m thick injection zone at approximately 3.2 km depth in a fluvial sandstone formation (lower Tuscaloosa Formation). The variation of pore fluid pressure was obtained during discrete events of fluid withdrawal from one of the two wells and monitored with downhole pressure sensors. The results indicate a correlation between decreasing CASSM time delay (i.e., velocity change for a raypath in the reservoir) and periods of reduced fluid pore pressure. The correlation is interpreted as the velocity-stress sensitivity measured in the reservoir. This observation is consistent with published laboratory studies documenting a velocity ([Formula: see text]) increase with an effective stress increase. A traveltime change ([Formula: see text]) of 0.036 ms is measured as the consequence of a change in pressure of approximately 2.55 MPa ([Formula: see text]). For [Formula: see text] total traveltime, the velocity-stress sensitivity is [Formula: see text]. The overall results suggest that CASSM measurements represent a valid technique for in situ determination of velocity-stress sensitivity in field-scale monitoring studies.


2021 ◽  
Vol 73 (1) ◽  
Author(s):  
Kodai Nakagomi ◽  
Toshiko Terakawa ◽  
Satoshi Matsumoto ◽  
Shinichiro Horikawa

An amendment to this paper has been published and can be accessed via the original article.


2019 ◽  
Vol 767 ◽  
pp. 228168 ◽  
Author(s):  
Melodie E French ◽  
Greg Hirth ◽  
Keishi Okazaki

2012 ◽  
Vol 117 (B5) ◽  
pp. n/a-n/a ◽  
Author(s):  
Luca Malagnini ◽  
Francesco Pio Lucente ◽  
Pasquale De Gori ◽  
Aybige Akinci ◽  
Irene Munafo'

Geology ◽  
2018 ◽  
Vol 46 (4) ◽  
pp. 299-302 ◽  
Author(s):  
Jiyao Li ◽  
Donna J. Shillington ◽  
Demian M. Saffer ◽  
Anne Bécel ◽  
Mladen R. Nedimović ◽  
...  

Water ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1784 ◽  
Author(s):  
Heping Shu ◽  
Jinzhu Ma ◽  
Haichao Yu ◽  
Marcel Hürlimann ◽  
Peng Zhang ◽  
...  

Debris flows that involve loess material produce important damage around the world. However, the kinematics of such processes are poorly understood. To better understand these kinematics, we used a flume to measure the kinematics of debris flows with different mixture densities and weights. We used sensors to measure pore fluid pressure and total normal stress. We measured flow patterns, velocities, and depths using a high-speed camera and laser range finder to identify the temporal evolution of the flow behavior and the corresponding peaks. We constructed fitting functions for the relationships between the maximum values of the experimental parameters. The hydrographs of the debris flows could be divided into four phases: increase to a first minor peak, a subsequent smooth increase to a second peak, fluctuation until a third major peak, and a final continuous decrease. The flow depth, velocity, total normal stress, and pore fluid pressure were strongly related to the mixture density and total mixture weight. We defined the corresponding relationships between the flow parameters and mixture kinematics. Linear and exponential relationships described the maximum flow depth and the mixture weight and density, respectively. The flow velocity was linearly related to the weight and density. The pore fluid pressure and total normal stress were linearly related to the weight, but logarithmically related to the density. The regression goodness of fit for all functions was >0.93. Therefore, these functions are accurate and could be used to predict the consequences of loess debris flows. Our results provide an improved understanding of the effects of mixture density and weight on the kinematics of debris flows in loess areas, and can help landscape managers prevent and design improved engineering solutions.


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