The Jackson School has a long tradition of leadership in fundamental and applied studies of liquid and solid water. Our research addresses broad questions such as: How is water distributed and routed through the Earth’s surface and subsurface? What are the impacts of human activities on water resource availability and quality? How are different components of the Earth system including the biosphere linked, and what is the role of water in these linkages? How will the hydrosphere and cryosphere respond to climate change? Researchers use complementary high-performance computing, laboratory experiments and measurements, and intensive field work in order to address these questions.
Hydrogeologists and hydrologists in the Jackson School have expertise in aqueous and microbial geochemistry, isotope geochemistry, physical hydrogeology, surface water hydrology, vadose zone hydrology, ecohydrology, and hydrogeophysics. Glaciologists in the Jackson School have expertise in ice sheet evolution and dynamics, supra-, sub- and englacial hydraulic systems, and the geologic setting of ice sheets.
Jackson School researchers and students are currently investigating hydrogeologic and glacial processes around the world. Some of our studies are conducted in Greenland, Antarctica, the Pacific Islands, Australia, Mexico, Chile, Switzerland, Egypt, and China, in addition to studying the hydrogeology of Austin’s interesting karst landscape and other parts of Texas. Some researchers also study ice sheets and potential water flow paths on Mars and Europa.
Faculty & Research Scientists
|Jay L Banner|
Isotopic methods, groundwater, oceans, ancient oceans, climate change, aquifers, caves, environmental science, geochemistry, paleoclimatology
|Philip C Bennett|
Aqueous geochemistry, geomicrobiology, environmental and microbial geochemistry, hydrogeology
|Daniel O Breecker|
The Breecker Group studies biogeochemical processes occurring at or near the land surface. We study soils and paleosols, caves and stalagmites, and other materials, such as volcanic glass, that give us insight into ancient Earth. We study timescales ranging from seasonal cycles to hundreds of millions of years. We use observations, mathematical models and both laboratory and field-based experiments to address an evolving range of questions. To learn more about the research we are doing, ...
|M Bayani Cardenas|
Hydrology and Hydrogeology
|Ian J Duncan|
Expertise in geomechanic and geochemistry applied to: risks associated with CO2 sequestration; hydraulic fracturing for shale gas production; environmental impact of hydraulic fracturing; and the water-energy nexus. Current research focuses on the scientific, environmental and public policy aspects of unconventional natural gas production, the water-energy nexus, and carbon capture and storage. He has a particular interest in risk analysis, decision making, and legal/regulatory issues related to fracing, CO2 sequestration, CO2-EOR, and energy production.
|Peter B Flemings|
Stratigraphy, basin analysis, basin-scale fluid flow, pore pressures in seafloor sediments, submarine landslides, oil and gas migration, methane hydrates, Integrated Ocean Drilling Program (IODP)
|Herbert S Hamlin|
Stratigraphy, sedimentology, and depositional systems integrating subsurface data (geophysical logs and cores) with outcrops. Applications in hydrogeology and petroleum geology.
|Seyyed Abolfazl Hosseini|
Research interests are mainly topics related to fluid transport in porous media. Current research includes: Enhanced Oil Recovery - Enhanced Gas Recovery - Upscaling and Upgridding - Above Zone Monitoring Interval - Reservoir Simulation and History Matching - Unconventional Reservoirs
|Susan D Hovorka|
Geologic carbon sequestration in deep sedimentary environments as part of carbon capture and storage. PI of the Gulf Coast Caron Center (www.gulfcoastcarbon.org) focused on research relevant to commercial development of geologic sequestration in regions where it is both needed and possible. Monitoring field projects. Petrography and sedimentology supporting hydrogeology in karst and contaminated systems. K-12 and public outreach and education.
|Joel P Johnson|
Process geomorphology, feedbacks between channel morphology and hydrology and sediment transport, landscape sensitivity to climate and lithology, bedrock river erosion, flash floods, arroyo erosion, canyon formation, environmental monitoring and sensor networks, laboratory flume experimentation, numerical modeling, tsunami sediment transport and deposition.
Permafrost, Antarctica, Planetary geology, Mars, Geomorphology, Remote Sensing, GIS
|Ashley M Matheny|
Ecohydrology, Bio- and Micro-meteorology, Vegetation Hydrodynamics, Watershed Hydrology, Land-Atmosphere Interactions, Biogeochemistry, Water and Carbon Cycles, and Modeling
Sedimentary Geology, Sedimentology, Stratigraphy, Geomorphology, Rivers, Deltas, Coastlines, Submarine Channels, Geohazards, Sediment-Gravity Currents, Sediment Transport, Seismic Interpretation, Basin Analysis
Subsurface hydrology, numerical modeling and optimization of groundwater resources, multiphase flow and contaminant transport in both the unsaturated and saturated zones, geochemistry modeling and subsurface reactive transport, Mathematical geology, geostatistics, inverse modeling, optimization, risk assessment and risk analysis
|Jeffrey G Paine|
Near-surface geophysics in hydrogeology and environmental and Quaternary geology; coastal geology; Quaternary geology and geomorphology; computer applications in the geological sciences
Multi-scale pore system characterization; Fluid flow in porous media; Unconventional reservoir
|Daniella M Rempe|
Hydrology, Geomorphology, Ecohydrology, Catchment Hydrology, Near-surface Geophysics, Hydrogeology
|Bridget R Scanlon|
Evaluation of the impact of climate variability and land use change on groundwater recharge, application of numerical models for simulating variably saturated flow and transport, controls on nitrate contamination in aquifers
|Timothy M Shanahan|
Paleoclimatology, paleoceanography, paleolimnology, sedimentary geology and geochemistry, organic geochemistry, isotope geochemistry, compound-specific stable isotope analysis
|Krista M Soderlund|
Astrobiology, Cryosphere, Geophysical Fluid Dynamics, Magnetohydrodynamics, Planetary Science
Subjects: Carbon sequestration, hydrological modeling, computational geoscience, fracture/fault modeling Skill sets: Geostatistical modeling, inversion and optimization algorithms, numerical modeling, web-based decision support systems Programming: Matlab, Python, Fortran, C, ArcGIS
|Matthew M Uliana|
Water resources, low-temperature aqueous geochemistry, groundwater modeling, environmental compliance
Dr. Yang's primary research interest is to understand the exchanges of momentum, radiation, heat, water, carbon dioxide, and other materials between the atmosphere and the Earth surface spanning from small (short) to very large (long) scales. This includes analysis of in-situ and remotely-sensed data for the Earth's surface, and modeling studies of weather, climate and hydrology at local, regional and global scales.
Methane Hydrate, Hydrogeology, Flow and Transport in Porous Media, Analytical and Numerical Modeling
|Michael H Young|
Ecohydrology of arid and semiarid landscapes; groundwater recharge in both managed agriculture and natural (arid and semi-arid) systems; influence of soil structure and vegetation on water cycling; design and implementation of monitoring systems for above-ground and near-surface below ground environments.
|Duncan A Young|
Ice-rock physical interactions in an ice cap context, tectonic evolution of the younger planetary crusts
|Feras A Habbal|
Adjunct/Emeritus Faculty‚Äč & Research Scientists
Permafrost, Antarctica, Planetary geology, Mars, Geomorphology, Remote Sensing, GIS
|John M Sharp|
Hyrdogeology; flow in fractured rocks; thermohaline free convection; fracture skin effects; regional flow in carbonate rocks; hydrology of arid and semi-arid zones; subsidence and coastal land loss; effects of urbanization; alluvial aquifers; hydrogeology of sedimentary basins;hydrological processes in ore deposit formation; and hydrogeophysics.
Geoscience education; Discipline Based Education Research (DBER); teacher professional development; geoscience curriculum development; undergraduate geoscience teacher preparation; climate literacy; geoscience, art and design engagement
|Rebecca C Smyth|
Current: Design and oversight of monitoring for CO2 at geologic sequestration sites; hydrogeologic characterization of industrial sites where subsurface materials and groundwater have been contaminated or have the potential of becoming contaminated, including environmental assessment of sites impacted by petroleum exploration and production activities. Past: Light Detection and Ranging (LIDAR) and Global Positioning System (GPS) mapping, and hydrogeology of ash-flow tuffs,
With increasing concerns on global climate change, there has been a growing interest in the potential impacts of it to groundwater reservoirs along with the surface waters. My principal research interest is based on the interaction between these major reservoirs in regional and local scales with the emphasis on water balance, saltwater intrusion, and climate variability. Use of field observations, space driven data and coupled simulation models are the tools required to understand the major ...
|Stephen B Ferencz|
Baiyuan is currently applying geomechanical models to study thin-skinned fold and thrust belts system. The research will further our understanding of stress, strain and compaction behaviors in fold-and-thrust belts. Baiyuan also aims to comp up with an improved approach to predict pore pressure in compressional regions.
|Jamin S Greenbaum|
Matt studies fundamental questions about the physical, chemical, and biological processes which work together to control all aspects of groundwater and surface water. In particular, he is interested in the the dynamic processes present at the interfaces between groundwater and surface water.
I am interested in understanding the role of plant hydrodynamics on the hydrological cycle and land-atmosphere interaction. My graduate research seeks to represent the plant hydrodynamics in the large-scale land surface modeling, and explore the influence of plant hydrodynamics on the hydrological cycle.
|Michael T O'Connor|
I am most interested in the hydrologic and biogeochemical processes occurring at and near the surface of the Earth. I use field and laboratory techniques as well as numerical modeling to understand and represent these complex systems. My current research focuses on the variably saturated flow and nutrient transport dynamics of Arctic permafrost systems. I hope to use this work to help describe the mechanisms for terrestrial Arctic carbon export. I am also very interested ...
|Emily C Pease|
Emily is a first year Masters student in Energy and Earth Resources working with supervisor Suzanne Pierce. Her research interests include bridging disciplines between data science, hydrogeology, and GIS/remote sensing to address pressing water issues in Texas. Until early 2019, Emily had been with the USGS Texas Water Science Center as a hydrologist for three years, working on groundwater modeling, GIS, and Python programming for the Geospatial Sciences and Cyber Innovation Branch. Currently, she works ...
|Michelle A Pedrazas|
|Micaela Pedrazas Hinojos|
I seek to holistically approach different subsurface processes through the integration of various data ranging from large scale (remote sensing, geophysical surveys and well data) to pore scale (laboratory experiments, sandbox experiments). I desire to tackle the challenges associated with quantifying, monitoring and sustainably managing Earth's resources such as groundwater. Ultimately, I seek to learn all I possibly can in order to direct my skills and knowledge to help find innovative solutions to complex problems ...
|Evan J Ramos|
I am a second-year PhD student whose research focuses on the usage of stable isotopes, computational geochemistry, and hydrology to refine earth systems models for geochemical cycles. Whether deep in the crust or at the Earth's surface, I see the physics and chemistry of fluid-rock interactions as a unifying lens to probe whole-Earth geochemical cycles. [bold]My past projects include[/bold]: -Using thermodynamic modeling and garnet geochronology to infer amounts and rates of dehydration from ...
Logan is interested in the shallow subsurface and its interaction with terrestrial ecosystems. His graduate research seeks to identifying regions of the Earth in which rock moisture (groundwater existing beneath the soil but above the water table in weathered, fractured bedrock) is ecologically important and to quantify the hydrologic dynamics of the weathered bedrock zone in these regions using novel geophysical methods.
Fluid flow, solute transport and reactive transport through fractures
|Graduate and undergraduate research in geologic sequestration of CO2 (Graduate or Undergraduate)|
Gulf Coast Carbon Center supports a team of students and post docs working in geologic sequestration (deep subsurface long-duration storage) of the major greenhouse gas CO2, as a method to reduce release to the atmosphere. Student projects are wide ranging, from sedimentology to policy, linked in that they are 1) multidisciplinary and 2) applied to current issues. Students are typically jointly supervised by faculty in geology or petroleum geosystems engineering and staff at the GCCC. A class in geologic sequestration is offered in the fall some years.
Posted by: Susan Hovorka
|Prospective Students (Graduate or Undergraduate)|
Thank you for your interest in joining my research group! There are currently opportunities at all levels beginning in the Fall of 2016. I welcome the opportunity to work with students who have a strong academic record, quantitative skills, research and writing experience, and unquenchable curiosity and creativity. Our group focuses on spatial and temporal patterns of water movement in the near surface. If you're interested in joining the lab, please contact me directly (firstname.lastname@example.org) with a CV and a statement of your research experience and interests.
Posted by: Daniella Rempe
The Institute for Geophysics shares data from a range of aerogephysical missions flown over Antarctica.
UTIG has developed, maintained, and operated a suite of aerogeophysical instrumentation since the early 1990s with continual improvements since inception. The suite was installed aboard a Dehavilland DHC-6 ("Twin Otter") up to 2005 and aboard a Basler BT-67 (a version of DC-3T -- a Douglas DC-3 refitted with turboprop engines) since 2008. The current instruments are: High Capability Radar Sounder (HiCARS); Multibeam, Scanning Photon Counting Lidar; Cesium Vapor Magnetometer; Gravimeter; Dual-frequency, carrier-phase Global Navigation Satellite Systems (GNSS); Laser Altimeter; Two GPS-aided Inertial Measurement Units; Three-Axis Fluxgate Magnetometer; System Control, Data Acquisition, and Real-time QC and Monitoring functions.
|Analytical Geochemistry Lab|
|Aqueous Geochemistry Lab|
Characterizes the chemical properties of water and solids to support research in hydrogeology, geochemistry, and geomicrobiology. Equipment used: carbon analyzer (TC), Organic analysis Field and laboratory gas chromatographs, thermal desorber, high pressure liquid chromatographs, Inorganic analyses Ion chromatograph, autotitrator, field and lab spectrophotometers. BET sorptometer for N2, Ar, and Kr BET surface areas, and A microporosities, organic carbon analyzer.
Installed in 2002-2003, the JEOL JXA-8200 electron probe microanalyzer (EPMA) is equipped with five wavelength dispersive spectrometers (WDS), an energy dispersive detector (EDS), and two image detectors in secondary and backscattered electron modes. The primary aim of the microprobe is quantitative elemental analysis of minerals on a microscale with high precision (less than a percent relative for major constituents) and low detection limits (commonly a few tens to few hundreds ppm)
|Flash Flood & Tsunami Flume|
The Flash Flood and Tsunami flume is a large (approximately 40 x 1.5 x 0.8 m) outdoor flume with a computer-controlled headbox lift gate that generates reproducible flood bores. It is being used to study the hydraulics and sediment transport of rapidly changing hydrographs.
Facilities for culturing and characterizing aerobic and anaerobic prokaryotes (Eubacteria and Archaeabacteria) using a Coy anaerobic chamber (H2/N2 atmosphere), Constant temperature water baths, autoclave, incubator, horizontal and vertical gel rigs, refrigerated centrifuge, UV light box, Thermalcycler, phase-contrast and fluorescent microscope. HPLC and GC facilities for degradation studies.
|Geophysical Equipment for Glaciology|
We have a custom built, low-frequency, short-pulse, ground-based radar system to image deep (>100 m) internal layers and the base of the ice sheet. Frequencies used with this system include 1, 2, 5 and 10 MHz. We also have a GSSI high-frequency (100MHz) ground-based radar system which can be used in several configurations and with a range of antennae frequencies. In addition, we have 7 GNSS GPS units for high-precision positioning, as well as multiple data loggers and time-lapse cameras for use in glaciological settings.
|HR-ICP Mass Spectrometers|
Equipment available: Thermo Element2 HR-ICP-MS with ESI autosampler system for solutions; and Thermo Element2 HR-ICP-MS with Photonmachines Analyte G2 Excimer laser ablation system.
This lab is dedicated to hydrogeology and environmental geology courses. It has facilities for grain-size analyses, porosity/ permeability testing, and a wide variety of lab demonstration techniques. It is also used as the base for groundwater field methods courses.
These tools include: 1) Electrical Resistivity Meter. The AGI SuperSting R8 IP is an 8-channel resistivity and induced polarization imaging system specially designed for large surveys where speed of data acquisition is of essence. Can be used for land applications with 6 m spacing, underwater applications with 2 m spacing, or boat-towed surveys with 1 to 5 m spacing. 2) Infrared Camera. The FLIR ThermaCAM SC640 is a high-resolution thermal infrared camera. The portable handheld radiometer (7.5 to 13 micron wavelength) takes images at 640x480 pixels at rates of down to 16 Hz. The precision of the camera is 0.08 C.
|Ice Dynamics Model|
A 4' x 6' bench-top physical model simulating water flow under ice sheets and glaciers. Ice is represented by a transparent polymer. Water is injected below the "ice" at varying rates to observe the effects of discharge pulses on the channel geometry and surface motion of the "ice." Changes in discharge are designed to mimic a typical diurnal discharge pattern observed on alpine glaciers.
|Isoprobe ICP Mass Spectrometer|
The IsoProbe MC-ICP-MS is a multicollector, magnetic-sector inductively coupled plasma mass spectrometer featuring a hexapole collision cell immediately behind the interface region of the ICP, and the multicollector contains nine Faraday collectors, three channeltron ion-counting detectors for low-level signals (ion currents below 10-16 amp), and an axial Daly detector located behind a wide aperature retarding potential filter for high abundance sensitivity on the Daly detector. The IsoProbe mass spectrometer is capable of making isotope ratio measurements in a large number of systems, including Ca, Fe, Cu, Se, Rb-Sr, Sm-Nd, Lu-Hf, Re, common Pb, Th-U series isotopes, and in situ laser ablation measurements of Sr, common Pb, Lu-Hf, and U-Pb.
|Isotope Clean Lab (Banner)|
The Isotope Clean Lab is a 600 square foot clean chemistry lab with seven Class-100 workspaces for preparation of rock, mineral, soil, plant and water samples for chemical and isotopic analysis under low-contamination conditions.
|Narrow Temperature-controlled Open Channel Flume|
Custom built 5-m tilting flume. Width: 30 cm. Depth: 1 meter. Other features: 3 removable windows with septa ports, fluids can be extracted or injected from the floor.
|Quadrupole ICP Mass Spectrometer|
The Quadrupole ICP-MS laboratory (with laser ablation) is used for elemental determinations in a wide range of liquid (e.g., natural waters, dissolved sediments/rocks, digested biomass) and solid (e.g., rocks, minerals, glasses) samples. The ICP-MS instrument is an Agilent 7500ce, capable of measuring trace element concentrations in solution over a nine-order linear dynamic range, from ppt to 100s of ppm. Sample introduction systems include a Micromist concentric nebulizer with a Peltier-cooled spray chamber for aspirating solutions, and a New-Wave UP¨193-FX 193 nm excimer laser ablation system for micro-sampling of solids. Sub-ppm detection limits are obtained routinely by laser ablation. The Agilent 7500ce is equipped with a collision/reaction cell, allowing for quantification of environmentally important matrix/plasma-sensitive elements such as As, Se, and Fe. The instrument is housed in a positive-pressure HEPA-filtered laboratory equipped with a weighing station, laminar flow bench, and Type 1 (18.2 M?) ultrapure water station.
|R/V Lake Itasca|
UTIG owns and operates a 22' aluminum hulled research vessel, the R/V Lake Itasca. The Itasca is a custom built hull powered by twin 115 HP Honda outboard engines equipped with hydraulic steering. The vessel is equipped with a starboard side davit (Fig. 5) that has been used to deploy a variety of water column gear including CTDs, grab samplers, gravity corers, isokinetic water samplers and niskin bottle samplers. Generally the vessel operates in survey mode with a maximum of 3-5 persons onboard. The vessel is equipped with rack mounts that contain a Reson Seabat multibeam system. Other acoustic devices that have been towed by the Itasca include the UTIG CHIRP subbottom profiler, sidescan sonars, and acoustic Doppler current profilers. The R/V Lake Itasca has been used throughout the Gulf of Mexico in rivers, estuaries and the inner shelf in calm seas. It has also been transported as far afield as British Columbia (Fraser River). The vessel can be shipped worldwide in a standard shipping container.
|Revolving Environmental Lab|
The REL includes a geoprobe for drilling, an Ion Chromatograph for analyzing anions and cations, and a stratified aquifer sampler for analyzing varying groundwater flow and quality with depth.
|Scanning Electron Microscope Lab (DGS)|
Installed in 2008, this is a high-performance, 30 kV tungsten gun scanning electron microscope with a high resolution of 3.0 nm. The low vacuum mode allows for observation of specimens which cannot be viewed at high vacuum due to a non-conductive surface. This SEM has three detector systems - secondary electron (SE), backscattered electron (BSE), and X-ray EDS detectors.
|Stable Isotope Lab for Critical Zone Gases|
This lab is designed for the study of caves, soils and vegetative canopies. The GasBench II and Thermo Electron 253 in the High Temp. Stable Isotope lab are currently being used to measure the carbon isotope composition of soil and cave CO2, CO2 respired in soil respiration experiments, and dissolved inorganic carbon and calcium carbonates from multiple environments.
|UT Experimental Deep Water Basin|
The UTDW Basin is an experimental tank designed to physically model morphodynamic and stratigraphic evolution of continental margins and other subaqueous sediment transport systems. It is 4 m wide, 8 m long, and 2 m deep. The tank has 5 observation windows, underwater lighting and an array of synced overhead cameras. The facility is designed to map underwater deposit surfaces in space through time and measure fluid dynamic and sediment transport properties of formative density flows.
|Center for Integrated Earth System Science|
The Center for Integrated Earth System Science (CIESS) is a cooperative effort between the Jackson School of Geosciences and the Cockrell School of Engineering. The center fosters collaborative study of Earth as a coupled system with focus on land, atmosphere, water, environment, and society.
|Center for International Energy & Environmental Policy|
In 2005, the University of Texas at Austin chartered the Center for International Energy and Environmental Policy (CIEEP), to join the scientific and engineering capabilities of the University's Jackson School of Geosciences and the College of Engineering with the LBJ School of Public Affairs. The University's first center dedicated to energy and environmental policy, CIEEP will seek to inform the policy-making process with the best scientific and engineering expertise.
|Land, Environment & Atmospheric Dynamics|
The LEAD group consists of graduate research assistants, postdoctoral fellows, research scientists and visiting scholars. We view the earth system in a holistic way, linking the atmosphere, ocean, biosphere, cryosphere, and solid earth as an integrated system. We use powerful methodologies such as satellite remote sensing and supercomputing simulations which are now profoundly changing research in earth system sciences. We place a strong emphasis on the societal impact of the research in earth system sciences.
|Latin America & Caribbean Energy Program|
The Latin America & Caribbean Energy Program will create, foster and maintain a regional outreach network that will nurture cooperative and frank discussions of issues related to sustainable development of energy resources and environmental stewardship. The network will include representatives from governments, universities, private sector, multilateral agencies, industry and professional associations and other stakeholders.
Affiliated UT Programs & Centers
|Center for Frontiers of Subsurface Energy Security|
CFSES is one of only two centers out of 46 EFRCs with focus on subsurface energy. Our goal is a scientific understanding of the physical, chemical, and biological subsurface processes from the very small scale to the very large scale so that we can predict the behavior of CO2 and other byproducts of the energy production that may need to be stored in the subsurface. At this aim, we need to integrate and expand our knowledge of subsurface phenomena across scientific disciplines using both experimental and modeling methodologies to better understand and quantify the behavior at conditions far from equilibrium. The unique aspect of our research is the approach of the uncertainty and of the complexity of the fluids in the geologic media from the molecular scale to the basin scale and their integration in computational tools to better predict the long term behavior of subsurface energy byproduct storage.
|Center for Space Research|
The University of Texas at Austin, Center for Space Research was established in 1981 under the direction of Dr. Byron D. Tapley. The mission of the Center is to conduct research in orbit determination, space geodesy, the Earth and its environment, exploration of the solar system, as well as expanding the scientific applications of space systems data.
|Environmental Science Institute|
The Environmental Science Institute is a multi-disciplinary institute for basic scientific research in environmental studies founded by The University of Texas at Austin. The Institute serves as a focal point on campus for a wide scope of interdisciplinary research and teaching involving the complex interactions of the biosphere, hydrosphere, and lithosphere in the Earth system, as well as the human dimensions of these interactions.
|ENCOMPASS: Research for Earth-Society Systems|
|Jack Holt's Research Group|
Our research group is comprised of graduate students, undergraduates, technical staff and visiting students all focused on understanding both the current state of Mars ice and processes governing the distribution, history, and role of ice in Mars climate evolution. Our primary tool is orbital radar sounding, a technique that is relatively new for Mars, and for planetary exploration in general. Two radar sounders, MARSIS and SHARAD, are currently in orbit at Mars. Due to Dr. Holt's role as a Co-Investigator on SHARAD, we are very busy with the acquisition and analysis of new data. Building on UTIG's extensive experience in airborne radar sounding of ice on Earth, we have developed new analysis techniques specifically for SHARAD that give us unique capabilities and put us at the forefront of this exciting field.
Research at ZacatonPosted by Marcus Gary
Photos of research of the Sistema Zacaton karst area