Northeastern Mississippi Research Articles

A Simulation Model to Analyze the Impact of Outsourcing on Furniture Supply Chain Performance

As increasingly more companies outsource to Asia, US furniture companies' supply chains are becoming longer. To make their logistics networks more efficient, companies need to choose the right supply chain model, promote cooperation with their partners in the supply chain, and adopt new technologies to make better decisions and to manage better. Discrete-event simulation models are powerful tools that can be used by furniture manufacturers to perform what-if types of analyses to estimate the impact of their decisions on the overall performance prior to making any real changes to their system. We developed such a simulation model for a typical furniture manufacturer in northeastern Mississippi. By simulating the supply chain of the manufacturer under various scenarios, we show that outsourcing all of the business is not necessarily the best option because it may lead to a local reduction of capacity. This capacity reduction impacts the flexibility and profitability of the manufacturer. Outsourcing decisions may also be affected by product type. In general, outsourcing labor-intensive, slow-moving, and easy-to-transport items makes sense.

Long‐term change to fish assemblages and the flow regime in a southeastern U.S. river system after extensive aquatic ecosystem fragmentation

The upper Tombigbee River in northeastern Mississippi now exists as a fragment, confluencing with and fed by an extensively modified aquatic landscape now called the Tennessee‐Tombigbee Waterway (TTW). We examined the changes to fish assemblages and flow regime after waterway construction based on contemporary comparisons to historical fish collections and discharge data. The river's flow regime has changed markedly since TTW construction. Analysis of discharge data from two stations for 15 years, pre‐ and post‐waterway, indicated significant differences in flow regime including increased minimum and base flows, lower spring and higher late summer‐autumn flows, and lower high flow durations, post‐TTW. These changes corresponded to significantly reduced regional and local species richness, and strong shifts in fish assemblage structure across a 20 yr time span. Post‐waterway fish assemblages were related strongly to measured environmental variables characterizing local habitats. Several lentic‐adapted species increased their abundances in lower reaches of the river, including a recent invader to the TTW system, the Mississippi silverside Menidia audens. Fragmentation of river ecosystems via disruption to hydrologic regimes is a major threat to aquatic biodiversity worldwide. Because the flow regime of this fragmented river is in part controlled by waterway operations via five minimum flow control structures, adaptive conservation and management efforts could be implemented in order to maintain and potentially restore the natural flow regime and the ecological integrity of the system.

Prevalence of and risk factors associated with shedding of Cryptosporidium felis in domestic cats of Mississippi and Alabama

The prevalence of and risk factors associated with the shedding of cryptosporidial oocysts were determined for domestic cats in northeastern Mississippi and northwestern Alabama. Cryptosporidial oocysts were found in a single fecal samples from 30 of 250 cats using a centrifugal concentration technique followed by an immunofluorescent assay. The odds of a cat shedding oocysts were increased when another cat shedding oocysts was present in the household. Logistic regression analysis showed only concurrent shedding of Giardia cysts to be significantly associated with the presence of Cryptosporidium oocysts in the feces. Oocysts from 12 cats were successfully genotyped, based on sequencing of a fragment of the 18S rRNA gene, all isolates were Cryptosporidium felis.

CHARACTERIZATION OF A PETUNIA STRAIN OF TURNIP VEIN-CLEARING VIRUS

SUMMARY Virus-like symptoms were observed in February 2005 on Double Wave TM petunias (Petunia x hybrida Hort. Vilm.-Andr.) grown in a greenhouse in northeastern Mississippi. Electron microscope observations of leaf dips from symptomatic plants showed the presence of rodshaped virus-like particles. Infected petunia samples reacted weakly with an immunostrip test to Tobacco mosaic virus (TMV), but not in ELISA using a polyclonal antiTMV-c commercial kit. The dsRNA patterns from four infected petunias were identical and resembled those of tobamoviruses although they differed slightly in size from the replicative forms of TMV extracted from infected tobacco plants. Purified dsRNAs were used for random-primer cloning of the viral genome. A partial sequence of the viral 3’ end showed that the virus is a strain of Turnip vein-clearing virus (TVCV, reported also as Tobacco mosaic virus-crucifer strain) sharing 96% common nucleotides and 98% identical amino acids. To the best of our knowledge, TVCV has not been reported previously either from petunias or from Mississippi in general.

Integrated geophysical and geological investigation of a heterogeneous fluvial aquifer in Columbus Mississippi

A heterogeneous fluvial aquifer system exposed in a sand and gravel quarry outcrop in northeastern Mississippi was examined to quantify the relationship between geophysical attributes and lithostratigraphic properties. Two dimensional seismic reflection, ground penetrating radar, and DC resistivity profiles collected along the top of the quarry wall were compared with outcrop descriptions, photographs, and laboratory resistivity measurements and grain-size analysis conducted on a core collected near the center of the geophysical profiles. The aquifer is composed of an upper laterally continuous sandy-clay meandering fluvial system and a lower cross-bedded gravelly-sand braided fluvial system separated by a terrace. Seismic reflection data image the terrace, but depositional structures within the aquifer are below seismic resolution. These structures, including meter-scale channels and decimeter-scale channel-fill facies are imaged with ground penetrating radar , which correlates well with the outcrop and with the DC resistivity profile. The meandering fluvial facies is characterized by relatively low resistivity values (500–1250 Ω-m) and laterally continuous high-amplitude radar reflections. Lateral reflection terminations in the radar data indicate onlap at channel boundaries, which are filled with silty clay and clayey silt with very low resistivity values (50–400 Ω-m). The braided fluvial facies is characterized by higher resistivity values (1600–2600 Ω-m) and low-amplitude short bidirectional dipping radar reflections. Laboratory measurements of resistivity from a core collected along the quarry wall show a linear correlation to clay + silt content in all units within the meandering facies that have greater than 2% clay fraction, allowing surface DC resistivity data to be used as a predictor of clay + silt content in this facies. This is confirmed by comparison of predictions of clay + silt fraction based on the resistivity data to outcrop lithology. The combination of all three geophysical datasets is essential to fully characterize compartmentalization within this heterogeneous aquifer system.

REDISCOVERY OF THE GRAY BAT (MYOTIS GRISESCENS) IN NORTHEASTERN MISSISSIPPI

A male gray bat (Myotis grisescens) was discovered on private property in Tishomingo County, northeastern Mississippi, on 20 September 2004. The endangered gray bat previously had been known only from a site known as Chalk Mine in the northeastern corner of the county, where it was last documented in 1967. The 2004 specimen was recorded approximately 42 km south of the Chalk Mine site. The discovery of this specimen is noteworthy because it represents the first gray bat documented for the state of Mississippi in 37 years.

Timing bait applications for control of imported fire ants (Hymenoptera: Formicidae) in Mississippi: Efficacy and effects on non-target ants*

An experiment was conducted to assess the efficacy of mid-day (11:00 – 13:00 h) and late evening (18:00 – 20:00 h) broadcast bait (Seige Pro®, 0.73% hydramethylnon) applications against black and hybrid imported fire ants (Solenopsis richteri Forel and S. richteri × invicta, respectively) and their impact on native ant species. It was hypothesized that evening bait applications would have less impact on native ant species that slow or cease foraging at night relative to mid-day applications. Bait was applied to a series of plots in northeastern Mississippi, USA, in summer of 2002 and 2003. Population densities and foraging activity of imported fire ants and native ants were compared between treated and control plots. Population density and foraging activity of imported fire ants were equally suppressed in plots receiving mid-day and evening broadcast bait applications. Population density of Monomorium minimum (Buckley), the little black ant, approached zero in treated plots during 2003 but remained relatively high in untreated control plots. Species richness declined in treated plots with no difference between mid-day and evening bait application. These data indicate that evening bait application offers no advantage over mid-day application in terms of preserving some native ant species.

DENSITY AND DIVERSITY OF OVERWINTERING BIRDS IN MANAGED FIELD BORDERS IN MISSISSIPPI

Grassland bird populations are sharply declining in North America. Changes in agricultural practices during the past 50 years have been suggested as one of the major causes of this decline. Field-border conservation practices encouraged by the U.S. Department of Agriculture's National Conservation Buffer Initia- tive meet many of the needs of sustainable agriculture and offer excellent opportunities to enhance local grassland bird populations within intensive agricultural production systems. Despite the abundant information on avian use of, and reproductive success in, strip habitats during the breeding season, few studies have examined the potential value of field borders for wintering birds. We planted 89.0 km of field borders (6.1 m wide) along agricultural field edges on one-half of each of three row crop and forage production farms in northeastern Mississippi. We sampled bird communities along these field edges during February-March 2002 and 2003 using line-transect distance sampling and strip transects to estimate density and community structure, respectively. We used Program DISTANCE to estimate densities of Song (Melospiza melodia), Savannah (Passerculus sand- wichensis), and other sparrows along bordered and non-bordered transects while controlling for adjacent plant community. Greater densities of several sparrow species were observed along most bordered transects. However, effects of field borders differed by species and adjacent plant community types. Diversity, species richness, and relative conservation value (a weighted index derived by multiplying species-specific abundances by their re- spective Partners in Flight conservation priority scores) were similar between bordered and non-bordered edges. Field borders are practical conservation tools that can be used to accrue multiple environmental benefits and

Seasonal Migration and Overwintering Habitats of Chinch Bug (Hemiptera: Lygaeidae) in Northeastern Mississippi

The chinch bug, Blissns leucopterus leuco-pterus (Say), has become an important early-season pest of corn, Zea mays L., in the southeastern United States. Information on overwintering of chinch bugs is available but it is primarily from studies conducted in the central and midwestern states. Studies were conducted to describe chinch bug overwintering sites, changes in population densities in bromesedge, Andropogon virginicus L., and the timing of spring and fall flights from and to overwintering sites in a northeastern Mississippi environment during a three year period. Adults were found to over winter in many sites on the study area. High numbers of chinch bugs were found to congregate in bromesedge plants along roadsides or within cut-over woodland. Adults began to move into bromesedge for overwintering in September, but the largest increase occurred in October. Winter mortality from December to the end of February was slight probably because of mild winters during the three year study. Adult numbers in bromesedge began to decline in March as insects began to leave the overwintering site, and the rate of evacuation increased rapidly as temperatures warmed in April. Significant negative correlations were found to exist between the decline in numbers of chinch bugs in bromesedge and spring daily average and maximum temperatures. Fall and spring flight to and from overwintering sites based on captures of adults on aerial traps were found to be in general agreement with the timing of adult increase and decline on bromesedge.

Temporal Foraging Activity of Selected Ant Species in Northern Mississippi During Summer Months1

A study was conducted in northeastern Mississippi to examine temporal foraging activity of imported fire ants (Solenopsis spp.) and other common ant species that inhabit pasture and meadow. Baited vials were placed horizontally on the ground along straight-line transects (n = 21) every 3 h for 24 h periods during June–August. Vials remained on the ground for 30 min, then were quickly plugged with cotton and collected. Principal species captured in baited vials included Solenopsis spp. (black and hybrid imported fire ant) (90.6%), Solenopsis molesta (Say) (5.9%), Monomorium minumum (Buckley) (2.5%), Tapinoma sessile (Say) (0.7%), and Paratrechina vividula (Nylander) (0.3%). Imported fire ants foraged during all time periods, as did S. molesta and P. vividula. Tapinoma sessile and M. minimum slowed or ceased foraging at night. Forelius pruinosus (Roger) was captured on a single date while sampling at 1800 h. Implications for timing of bait applications against imported fire ants are discussed.

Mosquito and arbovirus activity during 1997-2002 in a wetland in northeastern Mississippi.

The species composition and population dynamics of adult mosquitoes in a wetland near Iuka, MS, were analyzed over a 6-yr period (1997-2002) and reverse transcription-polymerase chain reaction (PCR) detection rates of arboviruses determined during five of those years. Blood meals of three likely vector species were identified using a PCR-based method that allows identification of the host to species. Culex erraticus (Dyar & Knab) composed 51.9% of the population during the 6-yr period with 295 females collected per trap night. Eastern equine encephalomyelitis (EEE) virus was detected in six genera of mosquitoes [Coquillettidia perturbans (Walker), Culex restuans Theobald, Culex salinarius Coquillett, Culex erraticus (Dyar & Knab), Anopheles crucians Wiedemann, Anopheles quadrimaculatus Say, Aedes vexans (Meigen), Ochlerotatus triseriatus Say, and Psorophora ferox Humboldt) with positive pools occurring in 1998, 1999, and 2002. Culiseta melanura Coquillett occurred at a low level (< 1%) and was not infected. Saint Louis encephalitis virus was detected once in a single pool of Cx. erraticus in 1998. Neither West Nile virus nor LaCrosse virus was found. Minimum infection rates per 1000 females tested of competent vectors of EEE virus were variable and ranged from 0.14 for Cx. erraticus to 40.0 for Oc. triseriatus. Thirty-nine species of birds were identified in the focus with blood-engorged mosquitoes found to contain meals (n = 29) from eight avian species. The majority of meals was from the great blue heron, Ardea herodias L. (n = 55%), but when bird abundance data were adjusted for avian mass, the brown-headed cowbird, Molothrus ater (Boddaert); blue jay, Cyanocitta cristata (L.); and northern mockingbird, Mimus polyglottos (L.), were overrepresented as hosts.

Identification of possible Quaternary deformation in the northeastern Mississippi Embayment using quantitative geomorphic analysis of drainage-basin asymmetry

Research Article| May 01, 2001 Identification of possible Quaternary deformation in the northeastern Mississippi Embayment using quantitative geomorphic analysis of drainage-basin asymmetry Randel Tom Cox; Randel Tom Cox 1Department of Geological Sciences, 402 Smith Building, University of Memphis, Memphis, Tennessee 38152, USA Search for other works by this author on: GSW Google Scholar Roy B. Van Arsdale; Roy B. Van Arsdale 1Department of Geological Sciences, 402 Smith Building, University of Memphis, Memphis, Tennessee 38152, USA Search for other works by this author on: GSW Google Scholar James B. Harris James B. Harris 2Department of Geology, Millsaps College, Jackson, Mississippi 39210, USA Search for other works by this author on: GSW Google Scholar GSA Bulletin (2001) 113 (5): 615–624. https://doi.org/10.1130/0016-7606(2001)113<0615:IOPQDI>2.0.CO;2 Article history received: 10 Nov 1999 rev-recd: 19 Jun 2000 accepted: 30 Jun 2000 first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Randel Tom Cox, Roy B. Van Arsdale, James B. Harris; Identification of possible Quaternary deformation in the northeastern Mississippi Embayment using quantitative geomorphic analysis of drainage-basin asymmetry. GSA Bulletin 2001;; 113 (5): 615–624. doi: https://doi.org/10.1130/0016-7606(2001)113<0615:IOPQDI>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search nav search search input Search input auto suggest search filter All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract To investigate neotectonism in the Mississippi Embayment east of the New Madrid seismic zone, we identified geomorphic domains that show evidence of ground tilting during Quaternary time. Transverse basin profiles were converted to two-dimensional vectors that denote channel position with respect to basin divides. These basin-asymmetry vectors record the net direction and degree of lateral migration of trunk streams. More than 2500 vectors were measured and spatially averaged within 400 km2 bins. This field of 300 mean vectors delineates several domains that show preferred directions of stream migrations possibly driven by ground tilting. The timing of stream migration was interpreted using across-valley distributions of Quaternary alluvial terraces.Comparison of our mean vector field with subsurface structures suggests that some domain boundaries may be related to reactivated faults. Late Quaternary activity is suggested for two northeast-striking faults of the southeastern Reelfoot Rift margin. We acquired two seismic profiles showing near-surface faulting beneath scarps that follow the domain boundary associated with one of these northeast-striking faults (Big Creek fault zone). Reelfoot thrust seismicity ends on the south against this fault, suggesting that the rift margin has dextral slip accommodating northeastward movement of the thrust hanging wall. Our vector field also suggests late Quaternary movement on the Reelfoot thrust and on two other northwest-striking faults, here termed the Hatchie River fault and the Wolf River fault. Several other weak domains may imply minor elements of neotectonism. Our results demonstrate that morphometric analysis of drainage-basin asymmetry can be an effective reconnaissance tool within neotectonic settings. You do not currently have access to this article.

Abstract: Petroleum System of Lower Viosca Knoll and Northeastern Mississippi Canyon, Deepwater Gulf of Mexico

Abstract: Petroleum System of Lower Viosca Knoll and Northeastern Mississippi Canyon, Deepwater Gulf of Mexico

Phenology and spatial and temporal distribution of larval fishes in a partially channelized warmwater stream

AbstractWe studied the phenology and spatial and temporal dynamics of larval fish abundance with light traps from 5 locations along the length of Luxapalilia Creek, a partially channelized warmwater stream in northeastern Mississippi over 2 spawning seasops (March through August 1992 and 1993). The dominant, early spring spawners were catostomids (early‐April to late‐May) and darters (mid‐March to early‐June) whereas summer spawners were mainly cyprinids (mid‐May to August) and centrarchids (late‐May to August). The relative abundance of larvae collections differed based on: 1) site, 2) location, 3) date, 4) year, and 5) in larval stage. Total numbers of larvae and CPUE were high in mid‐ to late summer in downstream locations in both years when: 1) temperatures were high, 2) water velocities were low, and 3) depths were shallow compared to upstream locations. More mature larvae (meso‐ and metalarvae) were more common in the downstream locations whereas less mature larvae (yolk‐sac and protolarvae) were more abundant at the upstream locations. The downstream channelized portion of Luxapalila Creek resembled a lentic habitat with littoral zones characterized by slow water velocities, shallow depths, fine sediments, and vegetation. Larvae of darters (Etheostorna and Pcrcina), which require gravel bars and swift currents, were not collected in great numbers downstream, although members of the Ictiobinae (Carpoides and Ictiobus), cyprinidae and centrarchidae (Lepomis spp., Pomoxis spp. and Micropterus spp.) were more abundant downstream than upstream. This suggests that the natural, upstream locations acted as sources of larvae for the channelized downstream location.

Notes: Mitochondrial DNA Analysis Confirms the Existence of a Genetically Divergent Walleye Population in Northeastern Mississippi

Abstract Mitochondrial DNA analysis of 16 walleyes Stizostedion vitreum originating from Luxapalila Creek in northeastern Mississippi showed that they were genetically distinct (2.34% sequence variation) from walleyes collected from the Mississippi River basin and other northern drainages. There was no genetic variation among the 16 fish analyzed. This work confirms the existence of a unique genetic form of walleye in the Tombigbee River drainage, but further research is required to determine whether this distinct form occurs throughout the Gulf Coast drainages of Mississippi and Alabama. Because the genetic integrity of this southern walleye strain is threatened by stocking of northern walleye strains and by invasion of northern strains via the Tennessee–Tombigbee Waterway, a careful monitoring program with genetic markers should be implemented.

Regional Lithostratigraphy and Calcareous Nannofossil Biostratigraphy of the Arcola Limestone Member, Mooreville Chalk, of Eastern Mississippi and Alabama: ABSTRACT

ABSTRACT The Arcola Limestone, the upper member of the Mooreville Chalk of Mississippi and Alabama, is the most distinctive lithostratigraphic unit within the Mesozoic or Cenozoic outcrop belt of the eastern Gulf Coastal Plain area. Geographically, the Arcola extends from near Tupelo in northeastern Mississippi, about 365 km southeastward to near Downing in east-central Montgomery County, Alabama. The Arcola, which stratigraphically separates the Mooreville Chalk from the overlying and lithologically near identical Demopolis Chalk, varies in thickness from a few centimeters at its western and eastern termini to a maximum known thickness of 4.37 m at Hatchers Bluff along the Alabama River southwest of Selma, Dallas County, Alabama. Lithologically, the Arcola consists of from one to four beds of white to light-gray, bored and indurated calcisphere limestone, each varying from a few centimeters to a maximum of 0.8 m in thickness, separated by thin, moderately glauconitic and phosphatic, fossiliferous, quartzose silty chalky marl. In the shallow subsurface, the Arcola generally varies from 3 to 5 m in thickness and can be identified and mapped by its thin yet distinctive electric-log character. Further downdip, the electric-log marker as well as the characteristic light-color and indurated nature of the Arcola is no longer recognizable within the massive chalky marl of the Selma Group, yet the distinctive tiny calcispheres have been traced over a 30,000 km2 area of the Alabama Coastal Plain. Throughout its outcrop, as well as in numerous subsurface samples, the Arcola consistently lies within the uppermost few meters of the top of the lower Calculites ovalis Nannofossil Zone (CC19a) of middle Campanian age, thus representing the most geographically extensive time synchronous lithologic unit known within Mississippi or Alabama.

Cropping system influences on extractable water for mono- and double-cropped soybean

For rain-fed agriculture in the southeastern United States, efficient soil water use when double-cropping is essential. Water use by soybean [ Glycine max (L.) Merr.] following winter wheat ( Triticum aestivum L.) is, however, poorly documented. Winter wheat may deplete soil water, thus limiting subsequent soybean yield. Cropping system variables, such as soybean planting date and row spacing, may also affect water use. Therefore, a 4-year field experiment in northeastern Mississippi was conducted on Leeper ( Vertic Haplaquept) and Catalpa ( Fluvaquentic Hapludoll) silty clays. The objectives were to (1) determine the influence of soybean planting date, cropping system (monocropped versus double-cropped), and row spacing on extractable water (similar to available water) for soybean, and (2) identify a production system to improve the use of extractable water over a growing season. In mid- to late-May (the first soybean planting date), “Centennial” soybean in 38- or 76-cm rows was planted either between rows of standing wheat or in bare (monocropped) plots. After the wheat was harvested and the straw chopped, soybean was planted into bare soil or planted no-till into wheat stubble in mid-June for the second planting and in early July for the third. Soil water content was measured with a neutron probe from soybean emergence to maturity. Differences between each water content profile and a dry profile (constructed using the lowest recorded water content at each depth) were regarded as extractable water. Neither soybean planting date nor cropping system, as a main effect, exerted much influence on extractable water for soybean. As interacting factors later in the season, however, they were important. Plots with soybean in 38- rather than 76-cm rows contained more extractable water throughout the 1982 and 1983 seasons, and yielded over 9% more seed. Canopies closed about 20 days sooner with narrow rows than with wide rows. These full canopies protected and shaded the soil surface, probably reducing crusting and decreasing water losses by evaporation. We concluded that double-cropped soybean in 38-cm rows planted either into standing wheat in late May or into wheat stubble not later than mid-June utilized extractable water efficiently in silty clay soils in northeastern Mississippi.

Lack of salinity selection by freshwater and brackish populations of juvenile bluegill,Lepomis macrochirus rafinesque

Salinity preferences of juvenile bluegill (Lepomis macrochirus) from a freshwater pond in north-eastern Mississippi and a brackish bayou in coastal Mississippi held at 0‰ were tested at 26.5±1.0°C in salinity-gradient chambers (0, 2, 4, 6, 8, and 10‰) under a 12L∶12D photoperiod cycle. Juvenile bluegill from both sites did not show any statistically significant preference for any of the salinity options and were not significantly different from controls. These data suggest that juvenile bluegill from either locale fail to show any differential short-term (1.5 h) behavioral effects that might influence their perception and use of saline habitats. These data and data from previous studies suggest that bluegill are better able to physiologically and behaviorally tolerate elevated salinity relative to other centrarchids, particularlyMicropterus spp.

Oil and Gas Developments in Southeastern States in 1989

Total drilling activity in Mississippi, Alabama, Florida, and Georgia, including both exploratory and development wells, increased 72.5% from 608 wells in 1988 to 1049 wells in 1989. Most of the increase was a result of development drilling for coalbed methane in the Alabama portion of the Black Warrior basin. Exploratory drilling in 1989 in the southeastern states decreased 13.6%. Of the 229 exploratory tests in 1989, 55 were successful for a 24.0% success rate. This compares to 1988's 50 successful completions of 265 tests and an 18.9% success rate. The Paleozoic trend of northeastern Mississippi and northwestern Alabama accounted for 31.0% of the exploratory tests. This active trend had 13 new-field discoveries in 1989 compared with 17 in 1988. The Jurassic trend, with 22.3% of the total exploratory effort had 4 new-field discoveries in 1989 compared with 8 in 1988. The Upper Cretaceous trend accounted for 20.5% of the exploratory tests. This trend had 2 new-field discoveries in 1989, the same as in 1988. The Eocene, Lower Cretaceous, Oligocene, and Miocene trends accounted, respectively, for 16.2%, 5.2%, 3.9%, and 0.9% of the total exploratory tests. Four new-field discoveries were reported in the Eocene, 2 in the Lower Cretaceous, 2 in the Oligocene, and 2 in the Miocene.

Oil and Gas Developments in Southeastern States in 1988

Total drilling activity in Mississippi, Alabama, Florida, and Georgia, including both exploratory and development wells, increased 15.8% from 525 wells in 1987 to 608 wells in 1988. Exploratory drilling in 1988 in the southeastern states increased 29.9%. Of the 265 exploratory tests in 1988, 50 were successful for an 18.9% success rate. This compares to 1987's 47 successful completions of 204 tests and a 23.0% success rate. The Paleozoic trend of northeastern Mississippi and northwestern Alabama accounted for 34.0% of the exploratory tests. This active trend had 17 new-field discoveries in 1988 compared with 6 in 1987. The Jurassic trend, with 24.5% of the total exploratory effort, had 8 new-field discoveries in 1988 compared with 6 in 1987. The shallow Eocene Wilcox trend in southwestern Mississippi accounted for 16.6% of the exploratory tests. This trend had 3 new-field discoveries in 1988 compared to 5 in 1987. The Upper Cretaceous, Lower Cretaceous, and Miocene trends accounted, respectively, for 15.1%, 8.7%, and 1.1% of the total exploratory tests. Two new-field discoveries were reported in the Upper Cretaceous, 2 in the Lower Cretaceous, and 2 in the Miocene.