Geology topics

Research about Kentucky, Tennessee

Source-linked reports with geographic coverage including Kentucky, Tennessee.

At least 19 recordsLinked to original sources

USGS2025

A wetland for all seasons? Evaluating congruence in avian species richness and habitat associations within restored wetlands across the annual cycle

Wetland restoration on agricultural land to enhance wildlife habitat through the Wetland Reserve Easement (WRE) program has substantially increased wetland area within the Lower Mississippi Alluvial Valley (LMAV). Studies assessing avian response to wetland restoration often focus on specific communities during one season such as passerines in spring or waterfowl during winter. However, there is limited information on the extent to which restored wetlands provide habitat for distinct avian communities across the annual cycle. Our objectives were to quantify the extent to which avian species richness within a wetland was congruent across seasons and evaluate site covariates associated with avian use of WREs in the LMAV across multiple seasons. We calculated avian species richness in autumn, winter, and spring at 34 WREs across the LMAV in Kentucky and Tennessee during 2019–2021. We surveyed vegetation communities to evaluate site covariates that explained variation in avian species richness across sites. Avian species richness within a site was positively correlated between autumn and spring, but neither season was correlated with winter. No single covariate explained variation in avian richness across seasons but tree diameter was positively associated with avian species richness in both winter and spring. The presence of four distinct vegetation types (remnant forest, planted forest, natural regeneration forest, and herbaceous wetlands) was positively associated with avian species richness in winter. Our results indicate avian community response to site conditions varies across seasons and can inform future wetland restoration planning in the LMAV to provide habitat across the annual cycle.

Kentucky, Tennessee↗

USGS2025

Looking for Lazarus: Environmental DNA (eDNA) surveillance of the federally threatened Slender Chub (Erimystax cahini) in the Clinch and Powell Rivers

Erimystax cahni (Slender Chub) is a federally threatened fish native to the Powell, Clinch, and lower Holston rivers of Tennessee and Virginia. No individuals have been captured or reported for over 2 decades. We developed a species-specific environmental DNA (eDNA) assay to survey for its presence throughout its native distribution in new and historical sites. We detected Slender Chub eDNA in both the Powell and Clinch rivers in 3 of 43 sites sampled during summer 2022. The presence of live individuals could not be confirmed, and the detection of positive eDNA matches could result from pure individuals or hybrids. Note that positive eDNA matches do not preclude the presence of hybrid individuals; however, they can help guide managers to intensively sample areas with conventional methods (e.g., snorkeling and seining), which could improve the probability of capture of living individuals.

Kentucky, Tennessee↗

USGS2022

Preliminary models relating lake level gate operation and discharge at Reelfoot Lake in Tennessee and Kentucky

Preliminary models for gate operations at the new outlet control structure for Reelfoot Lake were developed by the U.S. Geological Survey, using calibrated ratings of the lift gates, to support the U.S. Fish and Wildlife Service in managing lake level. In 2018, the old structure at the outlet of Reelfoot Lake was buried and lake level control was transferred to a new structure. The transition from lake-level management of the old control structure to the new control structure was documented using historical lake level and discharge measurements and records of stop-log management from March 7, 2013, to August 12, 2018. Discharge into Running Reelfoot Bayou was determined using a standard stage-discharge rating curve. Discharge measured using an acoustic Doppler current profiler was used to calibrate gate-discharge equations for free and submerged orifice flow at the new structure. Two lake operation models, one for the summer season and another for the winter season, are provided for the new structure based on data from this period. The summer operation model is based on operation of the gates once the lake level exceeds an elevation of 282.7 feet (ft) above the North American Vertical Datum of 1988 (NAVD 88). Free flow begins when lake level reaches 282.3 ft above NAVD 88 and becomes transitional once the lake level exceeds 282.8 ft above NAVD 88. Submerged flow begins once the lake level reaches 283 ft above NAVD 88 and the tail-water depth is above critical flow depth. The winter operation model is based on operation of the gates once the lake level exceeds 283.2 ft above NAVD 88. Submerged flow begins when the lake rises to an elevation of 283.5 ft above NAVD 88 and the tail-water depth is above critical flow depth.

Kentucky, Tennessee↗

USGS2022

Density, harvest rates, and growth of a reintroduced American black bear population

Less than 30% of all species reintroductions have been successful and it is important that factors associated with success or failure be identified. Officials experimentally translocated 14 adult female American black bears ( Ursus americanus ) from Great Smoky Mountains National Park, North Carolina and Tennessee, USA, to Big South Fork National River and Recreation Area in the Cumberland Plateau of Kentucky and Tennessee, USA, in 1996–1997. Since that time, the reintroduced bear population has continued to expand in size and range so our study objective was to use spatially explicit capture-recapture methods across a wide spatial extent to estimate bear population abundance and growth. We constructed 440 (223 in KY, 217 in TN) hair traps in our primary sampling area in 2019 arranged in clusters of 4–9 traps/cluster, which we augmented with data from 138 hair traps in a secondary sampling area in Tennessee collected in 2018. We extracted and genotyped DNA from hair samples to construct spatially explicit capture histories, using spatial covariates to model inhomogeneous densities. Population abundance estimates across our 36,035-km 2 study area were 411 males and 406 females excluding cubs. Based on an initial standing population of 18 adult and subadult bears, the mean annual growth rate ( λ ) from 1998 to 2019 was 1.199. The mean annual harvest rate in Kentucky from 2013 to 2019 was 5.1% and in Tennessee from 2014 to 2019 was 13.2%. Based on simulations, the hunting seasons reduced mean λ from 1.217 to 1.199, but growth was rapid despite harvest. Genetic diversity was retained, with similar expected heterozygosity as in the source population. The lack of conspecifics, highly productive habitat, and an initial age and sex distribution that was skewed toward the most fecund members of the population likely contributed to the rapid growth and high levels of gene retention in this bear population.

Kentucky, Tennessee↗

USGS2018

Genetic structure in Elk persists after translocation

Elk ( Cervus canadensis ) translocation success is thought to be facilitated by high post‐release herd cohesion and limited movements; both should ensure genetic mixing following release. Such mixing is important to reduce potential effects of inbreeding or genetic drift, which can be especially important in small founding populations. We had a natural experiment where we could evaluate genetic mixing of 2 distinct lineages of elk after translocation to the same area. Founding elk ultimately came from north and south of a road barrier at Elk Island National Park (EINPN or EINPS, respectively), Alberta, Canada and the 2 groups were genetically distinct. During 2000 to 2003, elk originating from Elk Island National Park were translocated to Cumberland Mountains, Tennessee (TNCM) and Great Smoky Mountains National Park, North Carolina (GSMNP), USA (some elk spent time at Land Between the Lakes Recreation Area, Kentucky, USA, before their final translocation). At TNCM, translocated elk were hard released, whereas at GSMNP elk were held in pens up to 60 days before release (i.e., soft release). We hypothesized that associations formed in the source population would affect genetic structure in the future population. We predicted that matrilineal groups would stay closer together and have similar movements after translocation. We used 16 microsatellite markers to analyze genetic composition and structure of translocated elk and their offspring in the years after release. Most source elk used for translocation strongly assigned to either EINPN or EINPS (93.2%, n = 204). Evaluating the genetic structure of offspring after translocation, we found the 2 genetic groups mostly persisted ≥11 years following release. We measured the Euclidean distance between all possible pairs of telemetered female elk during each season and year and calculated the maximum distance moved from the release sites for females surviving >1 year. Mean Euclidean distances between pairwise locations of female elk were similar for each genetic cluster for each area. The mean distances for all paired locations (genetic clusters combined) in TNCM were 14.67 km ( n = 4,576 ± 13.23 [SD]) and in GSMNP were 9.30 km ( n = 1,468 ± 9.75). However, when looking at only simultaneous locations <50 m apart, the frequency of occurrence was higher ( P < 0.001) for elk with the same genetic structure (71.1%) compared with those with different structure (28.9%). The maximum distance travelled from the release site was not different for the 2 genetic groups, but EINPN females tended to travel farther. Pairwise female distances were lower in GSMNP where we used a soft release. Release methodology and social structure appear to affect movements and possibly genetic mixing after translocation. Given that restoration success can depend on maintaining genetic diversity and number of founders, our analyses suggest that within‐cluster breeding bias can result in lower genetic variability and a smaller effective population size than previously assumed.

Kentucky, Tennessee↗

USGS2015

Rapid growth and genetic diversity retention in an isolated reintroduced black bear population in the central appalachians

Animal reintroductions are important tools of wildlife management to restore species to their historical range, and they can also create unique opportunities to study population dynamics and genetics from founder events. We used non-invasive hair sampling in a systematic, closed-population capture-mark-recapture (CMR) study design at the Big South Fork (BSF) area in Kentucky during 2010 and Tennessee during 2012 to estimate the demographic and genetic characteristics of the black bear ( Ursus americanus ) population that resulted from a reintroduced founding population of 18 bears in 1998. We estimated 38 (95% CI: 31–66) and 190 (95% CI: 170–219) bears on the Kentucky and Tennessee study areas, respectively. Based on the Tennessee abundance estimate alone, the mean annual growth rate was 18.3% (95% CI: 17.4–19.5%) from 1998 to 2012. We also compared the genetic characteristics of bears sampled during 2010–2012 to bears in the population during 2000–2002, 2–4 years following reintroduction, and to the source population. We found that the level of genetic diversity since reintroduction as indicated by expected heterozygosity ( H E ) remained relatively constant ( H E(source, 2004)  = 0.763, H E(BSF, 2000–2002)  = 0.729, H E(BSF, 2010–2012)  = 0.712) and the effective number of breeders ( N B ) remained low but had increased since reintroduction in the absence of sufficient immigration ( N B(BSF, 2000–2002)  = 12, N B(BSF, 2010–2012)   = 35). This bear population appears to be genetically isolated, but contrary to our expectations, we did not find evidence of genetic diversity loss or other deleterious genetic effects typically observed from small founder groups. We attribute that to high initial genetic diversity in the founder group combined with overlapping generations and rapid population growth. Although the population remains relatively small, the reintroduction using a small founder group appears to be demographically and genetically sustainable.

Kentucky, Tennessee↗

USGS2012

Predicting ecological flow regime at ungaged sites: A comparison of methods

Nineteen ecologically relevant streamflow characteristics were estimated using published rainfall–runoff and regional regression models for six sites with observed daily streamflow records in Kentucky. The regional regression model produced median estimates closer to the observed median for all but two characteristics. The variability of predictions from both models was generally less than the observed variability. The variability of the predictions from the rainfall–runoff model was greater than that from the regional regression model for all but three characteristics. Eight characteristics predicted by the rainfall–runoff model display positive or negative bias across all six sites; biases are not as pronounced for the regional regression model. Results suggest that a rainfall–runoff model calibrated on a single characteristic is less likely to perform well as a predictor of a range of other characteristics (flow regime) when compared with a regional regression model calibrated individually on multiple characteristics used to represent the flow regime. Poor model performance may misrepresent hydrologic conditions, potentially distorting the perceived risk of ecological degradation. Without prior selection of streamflow characteristics, targeted calibration, and error quantification, the widespread application of general hydrologic models to ecological flow studies is problematic. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

Kentucky, Tennessee↗

USGS2011

A review of lignite resources of western Tennessee and the Jackson Purchase area, western Kentucky

This review of the lignite deposits of western Tennessee and the Jackson Purchase area in western Kentucky (Figure 1) is an updated report on part of the U.S. Geological Survey's National Coal Resource Assessment of the Gulf Coastal Plain Coal Province (see Ruppert et al., 2002; Hackley et al., 2006; Dennen, 2009; and other chapters of this publication). Lignite deposits of western Kentucky and Tennessee are an extension of the Gulf Coastal Plain Coal Province (Cushing et al., 1964), and currently are not economic to mine. These deposits have not been extensively investigated or developed as an energy resource. This review includes a description of the geology of the lignite-bearing units, a discussion of the available coal quality data, and information on organic petrology. Palynological data for lignite samples collected in Kentucky and Tennessee as part of this work are presented in Table 1. Lignite trace element data originally presented in Hackley et al. (2006) are not included in this report due to potential laboratory quality control issues during the time the samples were analyzed (U.S. Geological Survey Energy Resources Program, 2010).

Kentucky, Tennessee↗

USGS2002

Evaluation of 2-soft-release techniques to reintroduce black bears

Black bear ( Ursus americanus ) were extirpated from most of their range by the early 1900s by habitat destruction and unregulated hunting. Since then, bear habitat has recovered in many areas, but isolation may prevent natural recolonization. Black bear translocations often have limited success because of high mortality rates and low site fidelity. We tested 2 reintroduction techniques designed to overcome those problems. The first technique used a winter release whereby pre- or post-parturient female bears were removed from their dens and placed in new dens at the release area. The second technique involved translocating female bears to the reintroduction area during summer and holding them in pens for a 2-week acclimation period before release. We translocated 8 female bears with cubs with the winter-release technique and 6 female with the summer-release technique. After release, total distance moved, net distance moved, mean daily distance moved, and circuity for winter-released bears (x̄=18.3 km, 7.1 km, 1.4 km, and 0.36, respectively) were less than summer-released bears (x̄=97.6, 63.4 km 5.1 km, and 0.74; P =0.010, 0.040, 0.019, and 0.038, respectively). Also, survival of winter-released bears (0.88) was greater than that for summer-released bears (0.2, P=0.001). Population modeling indicated that the least one additional stocking of 6 adult females with 12 cubs would greatly increase chances of population reestablishment. the winter-release technique has distinct advantages over the summer-release technique, limiting post-release movements and increasing survival of translocated bears.

Kentucky, Tennessee↗

USGS1996

Base-flow data for the Little West Fork Basin, Fort Campbell, Tennessee and Kentucky, 1993 and 1994

Base-flow data were collected from selected sites within the Little West Fork basin during high and low base-flow conditions to support a study of the source and movement of ground water that supplies the Fort Campbell Military Reservation. Stream and spring discharge, water temperature, and specific-conductance data were collected during low base-flow conditions from 64 sites on September 1 and 13,1993, and again on October 18 and 19, 1994. High base-flow data were collected from 63 sites on March 17 and 18, 1994. Discharge was greater during high base-flow conditions than during low base-flow conditions. Major tributaries on the south side of the study area consistently had lower flow than the tributaries on the north side. Discharge data were used to categorize stream reaches and sub-basins. Stream reaches were categorized as gaining or losing, wet, dry, unobserved for each base-flow measurement period. More gaining stream reaches occurred during the high base-flow period than either of the low base-flow periods. More dry stream reaches occurred during the two low base-flow periods than during the high base-flow period. Sub-basin areas with surplus or deficient flow were also defined. Many areas of deficient flow occurred near the headwaters of the Little West Fork basin under all base-flow conditions. Fewer areas of deficient flow occurred near the mouth of the basin. The flow per square mile for each major tributary basin in the study area was also calculated. The values of flow per square mile for the Noah Spring Branch and Dry Fork Creek basins in the northern part of the study area were greater than those for the Piney Fork and Fletchers Fork basins in the southern part of the study area under all base-flow conditions.

Kentucky, Tennessee↗

USGS1989

Statistical analysis of factors affecting landslide distribution in the new Madrid seismic zone, Tennessee and Kentucky

More than 220 large landslides along the bluffs bordering the Mississippi alluvial plain between Cairo, Ill., and Memphis, Tenn., are analyzed by discriminant analysis and multiple linear regression to determine the relative effects of slope height and steepness, stratigraphic variation, slope aspect, and proximity to the hypocenters of the 1811-12 New Madrid, Mo., earthquakes on the distribution of these landslides. Three types of landslides are analyzed: (1) old, coherent slumps and block slides, which have eroded and revegetated features and no active analogs in the area; (2) old earth flows, which are also eroded and revegetated; and (3) young rotational slumps, which are present only along near-river bluffs, and which are the only young, active landslides in the area. Discriminant analysis shows that only one characteristic differs significantly between bluffs with and without young rotational slumps: failed bluffs tend to have sand and clay at their base, which may render them more susceptible to fluvial erosion. Bluffs having old coherent slides are significantly higher, steeper, and closer to the hypocenters of the 1811-12 earthquakes than bluffs without these slides. Bluffs having old earth flows are likewise higher and closer to the earthquake hypocenters. Multiple regression analysis indicates that the distribution of young rotational slumps is affected most strongly by slope steepness: about one-third of the variation in the distribution is explained by variations in slope steepness. The distribution of old coherent slides and earth flows is affected most strongly by slope height, but the proximity to the hypocenters of the 1811-12 earthquakes also significantly affects the distribution. The results of the statistical analyses indicate that the only recently active landsliding in the area is along actively eroding river banks, where rotational slumps formed as bluffs are undercut by the river. The analyses further indicate that the old coherent slides and earth flows in the area are spatially related to the 1811-12 earthquake hypocenters and were thus probably triggered by those earthquakes. These results are consistent with findings of other recent investigations of landslides in the area that presented field, historical, and analytical evidence to demonstrate that old landslides in the area formed during the 1811-12 New Madrid earthquakes. Results of the multiple linear regression can also be used to approximate the relative susceptibility of the bluffs in the study area to seismically induced landsliding.

Kentucky, Tennessee↗

USGS1988

Landslides triggered by earthquakes in the central Mississippi Valley, Tennessee and Kentucky

We mapped 221 large (more than 200 ft across) landslides of three morphologically distinct types on the bluffs bordering the Mississippi alluvial plain in western Tennessee and Kentucky Old coherent slides (146 landslides, or 66 percent of the total) include translational block slides and single and multiple-block rotational slumps, all of which are covered by mature vegetation and have eroded features; no active analogs exist in the area. Earth flows (51 landslides, or 23 percent of the total) are also largely revegetated and eroded, though a few active earth flows are present on bluffs that have been cleared of vegetation. Young rotational slumps (24 landslides, or 11 percent of the total) form solely along actively eroding near-river bluffs and are the only active or recently active landslides in the area. Two investigations conducted around 1900 indicate that the old coherent slides, in at least part of the area, formed during the 1811-12 earthquakes. The present investigation uses dendrochronology, geomorphology, historic topographic maps, local historical accounts, and comparisons with landslides triggered by other earthquakes to show that most or all of the old coherent slides and earth flows formed during the 1811-12 New Madrid earthquakes. Evidence clearly indicates that the only large, aseismic landslide activity in the area results from fluvial undercutting of near-river bluffs. This erosion of the base of the bluffs triggers slumps that are morphologically distinct from the old slumps on bluffs away from the river. Our conclusions are consistent with the findings of other recent investigations of the same landslides that indicate extensive seismic triggering of coherent slides and earth flows during the 1811-12 New Madrid earthquakes.

Kentucky, Tennessee↗

USGS1987

Construction, geologic, and hydrologic data for observation wells in the Reelfoot Lake area, Tennessee and Kentucky

Twenty-three observation wells were installed at 12 sites in the Reelfoot Lake area of Kentucky and Tennessee during July 1986. The wells were installed to supplement an existing water level network and to provide additional data on the hydraulic characteristics and vertical hydraulic gradients in the alluvial aquifer near Reelfoot Lake. Well yields ranged from less than 20 gallons per minute to about 140 gallons per minute. The specific capacities of the wells ranged from less than 1 to 17.1 gallons per minute per foot of drawdown. Three stratigraphic sequences were encountered during drilling. Clay and silty clay was about 40 feet deep near the southwest corner of Reelfoot Lake. Predominantly medium- to coarse grained sand occurred below about 15 feet of silt and clay near the west and northwest sides of Reelfoot Lake. Along the western limit of the study area, near Lake No. 9 and the Mississippi River, about 20 to 30 feet of silt and silty sand occurred below land surface.

Kentucky, Tennessee↗

USGS1984