RESEARCH
Our overarching research interests are on sedimentology, sequence stratigraphy, and diagenesis of carbonate and mixed carbonate-siliciclastic systems. Carbonates are very sensitive to environmental conditions, including climate, sea level, oceanography, water chemistry, water temperature, and geography, amongst others. Determining the relative importance of the various factors that can influence carbonate systems is a major focus of the research group.
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Our research approach is to start with rock data and then integrate data from other appropriate disciplines, such as paleontology, paleoecology, structure, geochemistry, and geophysics, that can help answer research questions. Data that are utilized range from large scale (seismic, outcrop) to small scale (micro-submicroscopic, detailed geochemistry).
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Current and future research projects are highlighted below. Most of these projects are concentrated on a common theme: What factors control development of low-latitude shallow-water transitional carbonate systems composed of complex and variable mixtures of photozoans and heterozoans? These specific types of low-latitude systems are of particular interest because they deviate from common perceptions of low latitude carbonates, they remain understudied and not well understood, and they form petroleum reservoirs, aquifers, and are potential targets for carbon sequestration.
CURRENT PROJECTS
Current projects are being conducted in two main areas: 1) Lower Mississippian rocks in the continental U.S., and 2) Oligocene-Miocene rocks in the Caribbean. Details for each project are provided below.
Lower Mississippian rocks in the continental U.S
Regional Controls on Low-Latitude, Shallow-Water Heterozoan and Photozoan Carbonate Facies Distribution, Lower Mississippian, Continental U.S.
The first phase of the project is to collect data from core and outcrop study, and integrate with data from published literature to look at distribution patterns of shallow-water marine heterozoan, photozoan and biosiliceous facies for different Mississippian time intervals across the continental U.S. Initial results indicate there are distinct paleogeographic distribution patterns of these major facies types across the continent.
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Documenting facies patterns on a regional scale is an important first step in understanding local-to-regional environmental factors that affect their distribution. The facies also have different reservoir characteristics. Understanding factors that control distribution can aid in predicting character of subsurface reservoirs and potential targets for CO2 storage.
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Click here for more details on this project.
Distribution of shallow-water inner-mid ramp heterozoan and biosiliceous facies in a low-latitude setting as a function of oceanographic conditions and paleogeography, Lower Mississippian, Kansas
Photozoan components typically abundant in low-latitude shallow water settings are notably absent in Lower Mississippian inner-mid ramp locations in low-latitude Midcontinent U.S. Instead the facies are dominated by heterozoan carbonate and biosiliceous facies, which indicate adverse conditions affected the photic zone.
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Kansas is a key area for detailed studies to better understand the factors that led to domination of heterozoan and biosiliceous components in shallow water settings. Lower Mississippian strata in Kansas form important reservoirs, so there is abundant subsurface data available for study.
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Subsurface well logs, cores, and structural data will be used to develop detailed maps of facies distribution in shallow water inner-mid ramp locations, refine paleogeography, and develop a sequence stratigraphic framework, with the goal of identifying the main environmental factors influencing deposition. Results will be useful for petroleum and carbon sequestration efforts as well.
Oligocene-Miocene rocks in the Caribbean
Miocene Research Group
Foraminifera expertise added to the group to Miocene research:
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Dr. Scott Ishman
KGS Senior Scientist/Associate Director
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Dr. Belkasim Kh. Khameiss, KGS Postdoctoral Scholar
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Research includes biostratigraphy and identification of benthic and planktonic foraminifera down to species and genre levels to aid in water depth and depositional environment interpretations and evaluating conditions under which foraminifera and associated taxa where deposited (e.g., nutrients, turbidity, temperature).
Effects of sea level and upwelling on development of a Miocene shallow-water tropical carbonate ramp system
We just recently published results from our studies in Puerto Rico. Click here to access the publication.
We continue expanding our outcrop-based studies, will incorporate subsurface core work study, and develop reservoir models in southern Puerto Rico.
Controls on Deposition and Reservoir Character of the Miocene Cicuco Field, NW Colombia: A Low-latitude Shallow-water Transitional Carbonate System
Recent presentation Click here
Depositional and Reservoir Character of Mixed Heterozoan-Large Benthic Foraminifera-Siliciclastic Sequences, Middle Miocene, Dominican Republic
Recent presentation Click here
Sequence Development of the Late Miocene Mixed Carbonate-Siliciclastic Cercado Formation, northwestern Dominican Republic ​
AAPG presentation Click here
The Role of Variable Paleotopography and Upwelling on Deposition of Late Oligocene and Miocene Heterozoan-Large Benthic Foraminifera-Coral Sequences
Recent presentation Click here
Depositional Environment and Water Depth Ranges for Oligocene-Miocene Kuphus (?incrassatus) bivalves in the Caribbean
GSA presentation Click here
OUR RESPONSIBILITY TO HELP REDUCING CO2 EMISSIONS
Within these current times of climate crisis and need for an energy transition, our group is also actively thinking of ways and participating in projects to reduce emissions of atmospheric CO2, a potent greenhouse gas.
We have an ongoing project focused on studying the potential of Mississippian rocks as a long-term CO2 subsurface sink (storage) in Kansas.
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Click here for more details on this project.
Future Projects
Future projects include studying modern shallow-water environments developed under adverse photic zone conditions in Puerto Rico which could serve as an analog model for subsurface studies such as Cenozoic and Mississippian systems. Another project we are looking at is investigating the suitability of low-magnesium fossil content in cores from Kansas and Colombia for strontium isotope dating with the goal of improving age resolution and correlations throughout the area which in turn will allow for evaluation of processes affecting depositional history.
Developing Modern Analog Models for Shallow-water Tropical Systems with Adverse Photic Zone Conditions, Puerto Rico
Studying modern carbonate systems and developing appropriate models are crucial for understanding the rock record, especially for those ancient shallow-water tropical systems developed under adverse photic zone conditions. These systems are not yet well understood in the rock record.
Puerto Rico is an ideal place for study because its variable development of photozoan (e.g., corals) and heterozoan (e.g., snails) biota in shallow-water photic zone environments around the island as a result of natural and human-induced variations in nutrients, turbidity, water chemistry, energy and water temperature. Lessons from modern Puerto Rico could be applied to similar reservoir systems throughout the rock record including Cenozoic in the Caribbean and Indo-Pacific and Mississippian in Kansas.
We are collaborating with the University of Puerto Rico-Mayaguez and seeking funding from the National Science Foundation and other institutions.
Click here for more details on this project.
Using Strontium Isotopes for Improving Age Dating of Mississippian strata in Kansas and Oligocene-Miocene strata in Colombia
Investigating the potential of fossil material including bivalves, brachiopods, and serpulids for strontium-isotope dating of Mississippian strata in Kansas and Oligocene-Miocene strata in Colombia.
Skeletal material will be analyzed for diagenetic alteration prior to strontium dating using several techniques (Click here to access Ortega-Ariza et al., 2015 publication for specifics).
