Parameters controlling sonic velocities in a mixed carbonate‐siliciclastics Permian shelf‐margin (upper San Andres formation, Last Chance Canyon, New Mexico)

Geophysics ◽  
1997 ◽  
Vol 62 (2) ◽  
pp. 505-520 ◽  
Author(s):  
Jeroen A. M. Kenter ◽  
F. F. Podladchikov ◽  
Marc Reinders ◽  
Sjierk J. Van der Gaast ◽  
Bruce W. Fouke ◽  
...  
Keyword(s):  
New Mexico ◽  
Velocity Ratio ◽  
Acoustic Properties ◽  
Carbonate Content ◽  
Sonic Velocity ◽  
Carbonate Minerals ◽  
Data Set ◽  
San Andres ◽  
Mixed Carbonate ◽  
Mineralogic Composition

We have measured the acoustic properties and mineralogic composition of 48 rock specimens from mixed carbonate‐siliciclastic outcrops of the Permian upper San Andres formation in Last Chance Canyon, New Mexico. The goals were: (1) identify and model the parameters controlling the sonic velocities; (2) assess the influence of postburial diagenesis on the acoustic velocities. The variation in sonic velocity in the 0 to 25% porosity range is primarily controlled by porosity, and secondly by the ratio of carbonate‐siliciclastic material. Linear multivariate fitting resulted in a velocity‐porosity‐carbonate content transform that accurately predicts sonic velocity at different effective stresses. The slope of the velocity‐porosity transform steepens with increasing carbonate content, which may be explained by the higher velocity of carbonate minerals. Another reason may be the property of carbonate minerals to form more perfect intercrystalline boundaries that improve the transmission properties of acoustic waves and are less sensitive to changes in effective stress. The velocity ratio [Formula: see text] is an excellent tool to discriminate between predominantly calcitic lithologies (ratio between 1.8 and 1.95) and predominantly dolomitic and quartz‐rich lithologies (ratio between 1.65 and 1.8). Gardner's experimental curve overestimates, and the velocity‐porosity transforms by Wyllie and Raymer underestimate, the observed sonic velocities, probably because they do not account for variations in texture, carbonate mineralogy, and pore geometry. Petrographic observations show that postburial diagenesis is minor and does not seem to significanfly affect porosity. Therefore, the outcrop data set can be regarded as a proxy for the subsurface analog. These findings underline the significantly more complex acoustic behavior in mixed carbonate‐siliciclastic sedimentary rocks than in pure siliciclastics where mineralogic composition explains most of the observed relationships between porosity and sonic velocity.

scholarly journals Thermochronological transect across the Basin and Range/Rio Grande rift transition: Contrasting cooling histories in contiguous extensional provinces

Geosphere ◽  
2021 ◽  
Author(s):  
Michelle M. Gavel ◽  
Jeffrey M. Amato ◽  
Jason W. Ricketts ◽  
Shari Kelley ◽  
Julian M. Biddle ◽  
...  
Keyword(s):  
New Mexico ◽  
Rio Grande ◽  
Basin And Range ◽  
Main Phase ◽  
Rio Grande Rift ◽  
Data Set ◽  
Rapid Cooling ◽  
Spatiotemporal Trends ◽  
Modeling Software ◽  
San Andres

The Basin and Range and Rio Grande rift (RGR) are regions of crustal extension in southwestern North America that developed after Laramide-age shortening, but it has not been clear whether onset and duration of extension in these contiguous extensional provinces were the same. We conducted a study of exhumation of fault blocks along a transect from the southeastern Basin and Range to across the RGR in southern New Mexico. A suite of 128 apatite and 63 zircon (U-Th)/He dates (AHe and ZHe), as well as 27 apatite fission-track (AFT) dates, was collected to investigate the cooling and exhumation histories of this region. Collectively, AHe dates range from 3 to 46 Ma, ZHe dates range from 2 to 288 Ma, and AFT dates range from 10 to 34 Ma with average track lengths of 10.8–14.1 µm. First-order spatiotemporal trends in the combined data set suggest that Basin and Range extension was either contemporaneous with Eocene–Oligocene Mogollon-Datil volcanism or occurred before volcanism ended ca. 28 Ma, as shown by trends in ZHe data that suggest reheating to above 240 °C at that time. AHe and ZHe dates from the southern RGR represent a wider range in dates that suggest the main phase of cooling occurred after 25 Ma, and these blocks were not reheated after exhumation. Time-temperature models created by combining AHe, AFT, and ZHe data in the modeling software HeFTy were used to interpret patterns in cooling rate across the study area and further constrain magmatic and/or volcanic versus faulting related cooling. The Chiricahua Mountains and Burro Mountains have an onset of rapid extension, defined as cooling rates in excess of >15 °C/m.y., at ca. 29–17 Ma. In the Cookes Range, a period of rapid extension occurred at ca. 19–7 Ma. In the San Andres Mountains, Franklin Mountains, Caballo Mountains, and Fra Cristobal range, rapid extension occurred from ca. 23 to 9 Ma. Measured average track lengths are longer in Rio Grande rift samples, and ZHe dates of >40 Ma are mostly present east of the Cookes Range, suggesting different levels of exhumation for the zircon partial retention zone and the AFT partial annealing zone. The main phase of fault-block uplift in the southern RGR occurred ca. 25–7 Ma, similar to what has been documented in the northern and central sections of the rift. Although rapid cooling occurred throughout southern New Mexico, thermochronological data from this study with magmatic and volcanic ages suggest rapid cooling was coeval with magmatism in the Basin and Range, whereas in the Rio Grande rift cooling occurred during an amagmatic gap. These observations support a model where an early phase of extension was facilitated by widespread ignimbrite magmatism in the southeastern Basin and Range, whereas in the southern Rio Grande rift, extension started later and continues today and may have occurred between local episodes of basaltic magmatism. These differences in cooling history make the Rio Grande rift tectonically distinct from the Basin and Range. We infer based on geologic and thermochronological evidence that the onset of extension in the southern Rio Grande rift occurred at ca. 27–25 Ma, significantly later than earlier estimates of ca. 35 Ma.

Seismic models of a mixed carbonate‐siliciclastic shelf margin: Permian upper San Andres Formation, Last Chance Canyon, New Mexico

Geophysics ◽  
2001 ◽  
Vol 66 (6) ◽  
pp. 1744-1748 ◽  
Author(s):  
J. A. M. Kenter ◽  
G. L. Bracco Gartner ◽  
W. Schlager
Keyword(s):  
New Mexico ◽  
Cross Section ◽  
Cross Sections ◽  
Phase Changes ◽  
Genetic Sequence ◽  
Sequence Boundaries ◽  
Seismic Models ◽  
Seismic Reflections ◽  
San Andres ◽  
Mixed Carbonate

Seismic models based on randomly distributed samples from the Permian upper San Andres Formation (Last Chance Canyon, New Mexico) verify that the most prominent seismic reflections are related to stratal geometry. However, at least some reflections arise from lateral facies transitions that are commonly associated with highly prograding mixed carbonate‐siliciclastic sediments. Understanding seismic reflections and reflection terminations in sedimentary rocks requires simulation of at least 2‐D cross‐sections of the impedance distribution. To investigate the cause of reflections in strongly prograding mixed carbonate‐siliciclastic shelf margins, acoustic velocity and bulk density were measured on more than 60 plugs that spatially cover one higher order genetic sequence. The resulting impedance values were gridded and contoured, and the genetic sequence was repeated to create a cross‐section. Averaging impedance values for each lithofacies zone generated a second impedance cross‐section. Seismic models of both impedance cross‐sections revealed the following observations: (1) reflections associated with the sequence boundaries are subject to amplitude and polarity phase changes and (2) at least one reflection within the high‐order sequences is related to subhorizontal facies changes and is associated with two pseudounconformities. The contoured impedance model is suggested to closer resemble the true impedance function in outcrop and shows subtle vertical shifts and significantly higher impedance contrasts.

scholarly journals Estimation of Band-Tailed Pigeon Band Recovery and Population Vital Rates in Colorado, 1969–1981

2016 ◽  
Vol 7 (2) ◽  
pp. 369-376 ◽  
Author(s):  
Mark E. Seamans ◽  
Clait E. Braun
Keyword(s):  
New Mexico ◽  
Data Collection ◽  
Standard Error ◽  
Additional Data ◽  
Vital Rates ◽  
Data Set ◽  
Sierra Madre Occidental ◽  
Annual Survival ◽  
Sierra Madre ◽  
Additional Data Collection

AbstractData to inform population assessment of the Interior subspecies of band-tailed pigeon, Patagioenas fasciata fasciata (breeding range from Colorado and Utah south into Sierra Madre Occidental of Mexico), have been lacking despite substantial past banding efforts. We used a data set of more than 26,000 bandings from Colorado, with 3,500 live recaptures and 780 recoveries from the harvest of banded individuals to estimate annual survival, fidelity, and harvest rates. Most birds were harvested in Colorado (62%) followed by Mexico (18%); New Mexico (16%); Arizona (3%); and 1% or less each in California, Washington, and Utah. On average, each year 15% (range 0–30%) of surviving band-tailed pigeons did not return to Colorado. From 1969 to 1981 mean annual survival was 0.633 (standard error [SE] = 0.031) for hatch-year and 0.719 (SE = 0.016) for after-hatch-year birds, with a mean annual recovery rate of 0.015 (SE = 0.002) for hatch-year and 0.011 (SE = 0.001) for after-hatch-year birds. From 1970 to 1974, mean annual abundance of band-tailed pigeons in Colorado on 1 September was 59,911–88,290. These data provide a baseline for additional data collection for band-tailed pigeons in the range of the Interior subspecies.

Detrital zircon ages from Proterozoic, Paleozoic, and Cretaceous clastic strata in southern New Mexico, U.S.A.

2019 ◽  
Vol 54 (1) ◽  
pp. 19-32
Author(s):  
Jeffrey M. Amato
Keyword(s):  
New Mexico ◽  
Detrital Zircon ◽  
Rocky Mountain ◽  
Published Data ◽  
Data Set ◽  
Basement Rocks ◽  
Dakota Sandstone ◽  
Clastic Sedimentary ◽  
Detrital Zircon Ages ◽  
Combined Data

ABSTRACT U-Pb ages were obtained from detrital zircon grains from Proterozoic, Ordovician, Devonian, Pennsylvanian, and Cretaceous clastic sedimentary rocks in southern New Mexico and are compared to previously published data from Proterozoic, Cambrian, Permian, and other Cretaceous strata. This provides the first combined data set from most of the known pre-Cenozoic clastic formations in southern New Mexico, albeit in a reconnaissance fashion. Proterozoic quartzite, conglomerate, and lithic sandstone yield mostly 1.65-Ga zircon ages that were derived from the Mazatzal province, with minor 1.8–1.7-Ga zircon ages from the Yavapai province. The Cambrian–Ordovician Bliss Sandstone is dominated by Grenville-age grains and Cambrian grains inferred to be locally derived. Newly acquired ages from the Ordovician Cable Canyon Sandstone are dominated by 1.7–1.6-Ga Mazatzal province zircon grains, whereas new data from the Devonian Percha Shale indicate subequal contributions from 1.7–1.6-Ga and ~1.4-Ga sources, along with 1.8–1.7-Ga zircon ages. Both of these formations likely had mainly distal sources as the Precambrian basement in the region was largely buried by older Paleozoic strata. New data from a sandstone in the Pennsylvanian La Tuna Formation show mostly Yavapai grains and minor Paleozoic zircon grains, including Cambrian zircon grains sourced from the nearby Florida Mountains landmass postulated to have been exposed during Pennsylvanian time. The Permian ‘Abo tongue’/Robledo Mountains Formation of the Hueco Group has mostly Neoproterozoic and Grenville-age zircon grains and was derived from Ancestral Rocky Mountain uplifts that did not have a large ~1.4-Ga component. The Aptian Hell-to-Finish Formation of the Bisbee Group has mostly Yavapai-aged zircon grains in the pre-1000-Ma age group, but younger Albian- and Campanian-age sandstones have mostly Grenville-age zircon grains. New data from the Albian Beartooth Quartzite indicate syndepositional volcanic grains at 102 Ma and support correlations with the Mojado Formation rather than the younger Dakota Sandstone. Archean zircon ages are rare overall in all of the strata in southern New Mexico, but zircon grains with ages of ~2.74 Ga are most abundant. These grains could have been derived from basement rocks in the Wyoming or Superior provinces, or recycled from sediment originally derived from those sources.

scholarly journals Occupancy and habitat correlates of javelinas in the southern San Andres Mountains, New Mexico

2014 ◽  
Vol 95 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Louis C. Bender ◽  
Mara E. Weisenberger ◽  
Octavio C. Rosas-Rosas
Keyword(s):  
New Mexico ◽  
San Andres
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