scholarly journals Aspects of the Hydrogeology of southern Campeche and Quintana Roo, Mexico

2021 ◽  
Vol 73 (1) ◽  
pp. A011020
Author(s):  
Eugene C. Perry ◽  
Rosa M. Leal-Bautista ◽  
Guadalupe Velázquez-Olimán ◽  
Joan A. Sánchez-Sánchez ◽  
Nikklas Wagner
Keyword(s):  
Saturation Index ◽  
Indirect Evidence ◽  
Surface Flow ◽  
Quintana Roo ◽  
Interior Region ◽  
Deep Aquifer ◽  
Groundwater Aquifer ◽  
High Sulfate ◽  
Chicxulub Impact ◽  
Barton Creek

This paper explores strong indirect evidence for existence of a previously unrecognized deep groundwater aquifer in southern Quintana Roo, adjacent parts of Campeche, and (probably) northern Belize. The region contains rocks of Cretaceous-to-Holocene age, including: 1) an up-thrust block of the late Cretaceous carbonate known in Belize as the Barton Creek Formation, which is the oldest formation exposed in the Mexican Yucatán Peninsula, 2) the Cretaceous/Paleogene Albion Formation consisting of weakly consolidated Chicxulub impact air-fall deposits, 3) the Paleocene-Eocene Icaiche Formation, containing a massive 25-35 m thick gypsum member that crops out over an estimated area of more than 10,000 km2 in the elevated interior region of the northern lowlands, and 4) younger rocks of relatively low permeability that flank the region on the east. Hydrogeology is dominated by groundwater and surface flow in and adjacent to the Rio Hondo Fault Zone (RHFZ) and by recharge in the elevated interior region. Groundwater in the elevated region has a high sulfate concentration and is approximately saturated with gypsum dissolved from the Icaiche Formation. High-sulfate groundwater and river water with a slightly lower gypsum saturation index than in the elevated region also occurs in the RHFZ, but no water of comparably high sulfate content is present elsewhere in the study area. This suggests that the elevated region is a recharge zone for high-sulfate groundwater carried eastward beneath a 50 km gap by a deep, previously unrecognized aquifer and then discharged into the RHFZ. Based on chemistry of chloride, sulfate and other ions it is proposed here that a deep aquifer comprising the strongly weathered upper surface of the Barton Creek Formation plus the overlying weakly consolidated Albion Formation connects the elevated recharge area with the RHFZ discharge area. If this composite permeable zone does extend westward beneath the elevated recharge zone, it is probably an excellent aquifer.

scholarly journals Designing Aquifer Model for the Banks of the Serayu River, Sokawera, Somagede, Banyumas, Indonesia by Means of 1D-Electrical Resistivity Data

2021 ◽  
Vol 53 (3) ◽  
pp. 344-357
Author(s):  
Sehah Sehah ◽  
Hartono Hartono ◽  
Zaroh Irayani ◽  
Urip Nurwijayanto Prabowo
Keyword(s):  
Electrical Resistivity ◽  
Model Potential ◽  
Research Area ◽  
Shallow Aquifer ◽  
Shallow Aquifers ◽  
Clayey Sand ◽  
Deep Aquifer ◽  
Resistivity Data ◽  
Deep Aquifers ◽  
Groundwater Aquifer

A geoelectric survey using the 1D-electrical resistivity method was applied to design a groundwater aquifer model for the banks of the Serayu River in Sokawera Village, Somagede District, Banyumas Regency, Indonesia. The aim of this research was to identify the characteristics of aquifers in the research area based on resistivity log data. Acquisition, modeling, and interpretation of resistivity data were carried out and the results were lithological logs at seven sounding points. Correlation between the lithological logs resulted in a hydrostratigraphic model. This model is composed of several hydrological units, i.e. shallow aquifer, aquitard, and deep aquifer. The shallow aquifers are composed of sandy clay (10.81-18.21 Wm) and clayey sand (3.04-7.43 Wm) with a depth of groundwater from the water table to 27.51 m. The deep aquifers are composed of sandstone with variation of porosity (2.24-12.04 Wm) at a depth of more than 54.98 m. Based on this model, potential shallow aquifers were estimated to be at sounding points Sch-5, Sch-6, and Sch-7. This hydrostratigraphic model shows that the two types of aquifers are separated by an aquitard layer, allowing groundwater infiltration from the shallow aquifer to the deep aquifer and vice versa. Moreover, the Serayu riverbanks in this research area are estimated to be a groundwater discharge area.

scholarly journals HYDROGEOPHYSICAL DELINEATION OF PROLIFIC GROUNDWATER AQUIFER AROUND STUDENTS’ HOSTELS IN FUPRE CAMPUS, NIGERIA

2020 ◽  
Vol 4 (2) ◽  
pp. 68-72
Author(s):  
Alaminiokuma G.I. ◽  
Omigie J.I.
Keyword(s):  
Electrical Resistivity ◽  
Shallow Aquifer ◽  
Coarse Grained ◽  
Sand Column ◽  
Deep Aquifer ◽  
Current Electrode ◽  
Electrical Resistivity Survey ◽  
Groundwater Aquifer ◽  
Groundwater Supply ◽  
Coarse Grained Sand

Electrical resistivity survey was conducted around Students’ Hostels in FUPRE to delineate prolific aquifer for potable water to serve the teeming population of staff and students. Five vertical electrical soundings (VES) using Schlumberger electrode configuration with a maximum current electrode spread of 300m were employed for data acquisition. WINRESIST software was employed to execute the iteration and inversion processes of computing resistivities, depths and thicknesses of the various layers and the curve types. Results indicate that the area is characterized by 4 distinct geoelectric layers inferred differently at the VES locations. Two potential groundwater aquifer zones are delineated. The unconfined shallow aquifer zones found at VES 1, 3, 4 and 5 locations have shallow overburden depth ranging between 3.7-19.3m and coarse-grained sand columns with thicknesses ranging between 2.8-17.7m while the confined deep aquifer zone found at VES 2 location coincides with deep overburden layer at a depth of 42.6m and coarse-grained sand column with appreciable thickness of 19.1m. These results suggest that boreholes for sustainable groundwater supply around the Students’ Hostels should be sited at VES 2 location and screened at a depth ≥40.0m. However, aquifers at VES 1, 3, 4 and 5 have potentials for groundwater but are vulnerable to contamination. It is recommenced that electrical resistivity and hydrogeological surveys should be conducted at different locations in FUPRE, before any borehole(s) are drilled, to delineate the appropriate aquifer for potable groundwater supply and to avoid possible contamination.

Chicxulub impact ejecta deposits in southern Quintana Roo, México, and central Belize

2005 ◽  
Author(s):  
Kevin O. Pope ◽  
Adriana C. Ocampo ◽  
Alfred G. Fischer ◽  
Francisco J. Vega ◽  
Doreen E. Ames ◽  
...  
Keyword(s):  
Quintana Roo ◽  
Impact Ejecta ◽  
Chicxulub Impact

A new species of late Cretaceous crab (Brachyura: Carcineretidae) from Albion Island, Belize

1997 ◽  
Vol 71 (4) ◽  
pp. 615-620 ◽  
Author(s):  
Francisco J. Vega ◽  
Rodney M. Feldmann ◽  
Adriana C. Ocampo ◽  
Kevin O. Pope
Keyword(s):  
New Species ◽  
Late Cretaceous ◽  
Upper Cretaceous ◽  
The Other ◽  
Congeneric Species ◽  
Lower Maastrichtian ◽  
Chicxulub Impact ◽  
A New Species ◽  
Stratigraphic Range ◽  
Barton Creek

A new species of carcineretid crab, Carcineretesplanetarius, is described from the Upper Cretaceous (lower Maastrichtian) Barton Creek Dolomite at Albion Island, Belize. The age is based on the stratigraphic range of associated nerineid gastropods and correlation with nannoplankton, benthic foraminifera, and the other known congeneric species of crab found in Jamaica. Confirmation of this age aids in constraining the timing of ejecta deposits of the Chicxulub impact found at the top of Barton Creek Dolomite exposed on Albion Island. Paleoenvironmental and paleoecological analyses suggest that these crabs were swimmers in lagoonal settings, capable of burrowing a few centimeters into the mud for protection.

Efficacy of Crisis Intervention

Crisis ◽  
1999 ◽  
Vol 20 (2) ◽  
pp. 78-85 ◽  
Author(s):  
Thomas Reisch ◽  
Petra Schlatter ◽  
Wolfgang Tschacher
Keyword(s):  
Crisis Intervention ◽  
Intervention Program ◽  
Suicide Ideation ◽  
Indirect Evidence ◽  
Well Being ◽  
Term Therapy ◽  
Contributing Factors ◽  
Step Therapy ◽  
Long Term Therapy ◽  
The Impact

This study assesses the efficacy of the treatment approach implemented in the Bern Crisis Intervention Program, where particular emphasis is placed on the remediation of suicide ideation and suicidal behavior, and depression, fear, and phobia are generally considered to be contributing factors. Four questionnaires addressing psychopathology, emotional well-being, social anxiety, and personality were administered prior to and after the treatment of 51 patients over a period of 2 to 3 weeks. The reduction of symptoms contributing to suicidal ideation and behavior was interpreted as indirect evidence of an antisuicidal effect of the program. Significant improvements were found in the psychopathology ratings, with depression and anxiety showing the largest reductions. The impact on personality and social phobia, however, was only moderate, and on average patients still exhibited symptoms after attending the program. This residual symptomatology points to the necessity of introducing a two-step therapy approach of intensive intervention targeted at the precipitating causes of the crisis, augmented by long-term therapy to treat underlying problems.

Prevalence of Factor V Leiden Mutation in Non-European Populations

1997 ◽  
Vol 77 (02) ◽  
pp. 329-331 ◽  
Author(s):  
Guglielmina Pepe ◽  
Olga Rickards ◽  
Olga Camacho Vanegas ◽  
Tamara Brunelli ◽  
Anna Maria Gori ◽  
...  
Keyword(s):  
Factor V Leiden ◽  
Indirect Evidence ◽  
Factor V ◽  
Factor V Leiden Mutation ◽  
The World ◽  
Fv Leiden ◽  
Sub Saharan ◽  
Low Prevalence ◽  
European Populations ◽  
Apparently Healthy

SummaryA difference in the prevalence of venous thromboembolism (TE) in major human groups has been described and an uneven distribution of FV Leiden mutation over the world has recently been reported.We investigated FV Leiden mutation in 584 apparently healthy sub#jects mostly from populations different from those previously investi#gated: 170 Europeans (Spanish, Italians), 101 sub-saharan Africans (Fon, Bariba, Berba, Dendi), 115 Asians (Indonesians, Chinese, Tharus), 57 Amerindians (Cayapa), 84 Afroamericans (Rio Cayapa, Viche), and 57 Ethiopians (Amhara, Oromo).The mutation was detected in only 1/115 Asian (Tharu) and in 5/170 Europeans (4 Italians, 1 Spanish).These data confirm that in non-Europeans the prevalence of FV mutation is at least 7 times lower than in Europeans and provide indirect evidence of a low prevalence not only of the FV Leiden gene but also of other genes leading to more severe thrombophilia. Finally, findings from the literature together with those pertaining to this study clearly show a marked heterogeneity among Europeans.

Blood Viscosity and Platelet Aggregation in Male and Female Patients with Transient Ischaemic Attacks (TIA)

1979 ◽  
Author(s):  
G. Palareti ◽  
M. Poggi ◽  
G. Fortunato ◽  
S. Coccheri
Keyword(s):  
Platelet Aggregation ◽  
Blood Viscosity ◽  
Indirect Evidence ◽  
Vascular Lesions ◽  
Transient Ischaemic Attacks ◽  
Group A ◽  
Circulating Platelet Aggregates ◽  
Male Patients ◽  
Group B ◽  
Almost All

A series of 40 patients with TIA (25 males and 15 females) was thoroughly investigated by means of angiography and computerized tomography, and divided into a group (A) of 15 “sine materia”, and a group (B) of 25 with direct or indirect evidence of vascular occlusive or stenotic changes. Blood viscosity at 230 sec-1 37° was cp 4.2 ± 0.3 in the controls, cp 4.7 ± 0.7 in all patients (p < 0.05) cp 4.98 ± 0.7 in all male patients (p < 0.01 versus male controls), and cp 4.75 ± 0.8 in group B (p < 0.02). Haematocrit and Fibrinogen were also significantly increased in all male patients and in group B. Circulating platelet aggregates (CPA) were increased in 40% of the patients. Almost all patients with elevated CPA were males, with a slight prevalence in group B. Changes in blood viscosity parameters and in platelet aggregation in TIA patients were therefore related both to evidence of vascular lesions, and to sex, since they were found to prevail in male patients of both groups.

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