• Lead agency -- Delaware Geological Survey
• Cooperating State agencies -- Maryland Geological Survey, New Jersey Geological and Water Survey, Virginia Division of Geology and Mineral Resources
• Status -- Completed
• Please address inquiries to Peter McLaughlin (Delaware Geological Survey) or NGMDB staff.

The Delaware Geological Survey (DGS) has completed the first phase of a multi-state, multi- organization initiative aimed at establishing a regional understanding of the equivalencies of formation names across state lines in the Middle Atlantic Coastal Plain province (New Jersey- Delaware-Maryland-Virginia). This project, the Middle Atlantic Coastal Plain Stratigraphic Reconciliation Initiative or "MAtStrat", was developed as a cooperative effort of regional experts from state geological survey organizations, water resource agencies, universities, and the USGS. The DGS established an informal Middle Atlantic Coastal Plain Stratigraphy Working Group and coordinated workshops to identify important questions of stratigraphic equivalency between the states and to develop plans to resolve those questions. The results of the project are expected to benefit surficial geological mapping efforts in the region as well as the management of groundwater resources. It is hoped that the results support geological mapping efforts in the region by serving as a resource for the resolution of longstanding issues of formation name equivalencies at state boundaries where surficial geological maps created by different agencies can appear to conflict. The results also provide improved clarity of the equivalency of geologic names for groundwater-bearing formations between the states, allowing a better understanding of the connectivity of aquifer systems beneath these states. The project objectives, methodologies, and summary of results are outlined in a final project report. Draft correlation charts and regional cross sections will be released in final format after review with the participating state geological surveys. An extensive collaborative data store is accessible to participating organizations and researchers and will be migrated in 2024 to a more permanent cloud storage space.

• Lead agency -- Oregon Department of Geology and Mineral Industries
• Status -- Completed
• Please address inquiries to Mike Darin (DOGAMI) or NGMDB staff.

The published Oregon Geologic Data Compilation (OGDC, see publication) is not a traditional compilation map with consistent linework and geologic units across the state. Instead, it is a variable-scale collage of the best-available geologic mapping within the state, with their original linework and units retained. The previous version, OGDC-7, mosaiced 342 source maps with 7,240 source-map units. Source-map units were classified into a Terrane/Group–Formation–Member–Unit hierarchy and assigned values of rock type, age, and lithology that resulted in more than 2,000 unique compilation units.

Through this DOGAMI-USGS co-op project, we produced a new version 8 of OGDC (OGDC-8) and developed a consistent and working stratigraphic framework for Oregon. By assigning formal or informal Formation-level names to source-map units that were classified only at the Terrane/Group level in OGDC-7, this new OGDC-8 compilation reduces the Terrane/Group–Formation–Member–Unit hierarchy to a total of only 494 unique Formation-level map units that each correspond with one of 56 unique Terrane/Groups statewide. This effort allowed us to generate the first comprehensive stratigraphic correlation, or time-rock, charts for the state of Oregon. These new charts include five regional charts at the Formation level for NW Oregon, SW Oregon, the Cascade Range, NE Oregon, and SE Oregon, and a single chart at the Terrane/Group level for the entire state.

• The final technical report, including six regional correlation charts, will be published in 2024 as a DOGAMI Digital Data Series Release.

• Lead agency -- Geological Survey of Alabama
• Cooperating State agencies -- Florida Geological Survey, Mississippi Office of Geology
• Status -- In Progress; begun in 2021
• Please address inquiries to Sandy Ebersole (Geological Survey of Alabama) or NGMDB staff.

The Geological Survey of Alabama coordinated an East Gulf Coastal Plain Stratigraphic Working Group that allowed participating entities to cooperatively develop a consistent regional stratigraphic nomenclatural framework. This stratigraphic project supports USGS and State Geological Survey goals related to petroleum and groundwater issues.

During this project, two workshops were held and attended by representatives from Alabama, Mississippi, and Florida. Geologists on the three-state team also visited the field and examined well logs and core as part of the stratigraphic investigations. Comprehensive literature review included recent and historical publications, field and paleontological records, outcrop descriptions, and geologic maps from each state. These activities helped enrich discussions as the group worked toward stratigraphic revisions and deliverables. The Working Group generated a set of deliverables in fall of 2024.

The final project deliverables include a report that documents the nomenclature and nomenclatural history, lithology, age, and geographic extents of 250 geologic units; accompanying the report are 27 plates of stratigraphic charts and cross sections and 2 supplemental datasets documenting the units and geophysical well logs used in the cross sections. A discussion of recommended future multi-state stratigraphic investigations and mapping is also provided in the report.

The Working Group plans to publish the deliverables in 2025 as a Geological Survey of Alabama series publication. Additional single article publications are also planned.

• Progress report, 2022
• Progress report, 2023

• Lead agency -- Delaware Geological Survey
• Cooperating State agencies -- Maryland Geological Survey, New Jersey Geological and Water Survey, Virginia Division of Geology and Mineral Resources
• Status -- Completed
• Please address inquiries to Peter McLaughlin (Delaware Geological Survey) or NGMDB staff.

As a result of the initial finding of the MAtStrat I Cooperative, the Delaware Geological Survey conducted a MAtStrat II project to address unresolved issues in the stratigraphically complex late Miocene to early Pleistocene sediments in Middle Atlantic Coastal Plain from southeastern Virginia to Cape May, New Jersey. These strata contain important aquifers that are used by public water systems, agriculture, industry, and household consumers in the region, including growing municipalities with large summer tourist populations located along the Atlantic Coast. The project goal was to examine in detail all available core and sample material in the area to develop a regional stratigraphic framework of the units. This was accomplished by 1) collection of all available stratigraphic data both published and unpublished, 2) identification of available core material, 3) construction of regional cross sections, 4) a multi-state workshop to refine the cross sections and correlations, and 5) identification of additional work needed. Drilling was undertaken to address data gaps in critical areas. A 470-foot continuous wireline corehole was drilled in the middle of the region near Berlin, Maryland. Split-spoon coreholes were drilled further north nearer the Maryland-Delaware border and further south at the Maryland-Virginia border. Combined with the compilation of older data, the new cores clarify the nature of the north-to-south stratigraphic changes in the late Miocene to early Pleistocene sediments of the Delmarva Peninsula. In addition, the project served as an excellent opportunity to train university students in methods to describe sediment in detail, and to familiarize them with drilling techniques. The project objectives, methodologies, and summary of results are outlined in a final project report. Draft correlation charts and regional cross sections will be released in final format after review with the participating state geological surveys. The data assembled for this project is included in the same extensive collaborative data store as the MAtStrat I Project; it is accessible to participating organizations and researchers and will be migrated in 2024 to a more permanent cloud storage space.

• Lead agency -- Kansas Geological Survey
• Cooperating State agencies -- Iowa Geological Survey, Missouri Geological Survey, Nebraska Conservation and Survey Division, Oklahoma Geological Survey
• Status -- Completed, 2023
• Please address inquiries to Tony Layzell (Kansas Geological Survey) or NGMDB staff.

The midcontinent region of the United States (Kansas, Oklahoma, Missouri, Nebraska, and Iowa) has been a natural laboratory for the development of stratigraphic methods over the last 120+ years. This rich, long history has produced a voluminous literature that has been of great benefit to regional mining, aggregate, and petroleum industries. Unfortunately, however, the use, definition, and stratigraphic position of many Pennsylvanian rock units has varied between States and frequently changed through time, resulting in complexity and confusion in terms of stratigraphic nomenclature, correlation, and geologic mapping. The goal of this project was to develop a unified, regional understanding of Pennsylvanian stratigraphy across State boundaries. In order to achieve this goal, a regional working group, organized by the Kansas Geological Survey, was established. The group is composed of experts from geological surveys and academic institutions in Kansas, Missouri, Nebraska, Oklahoma, and Iowa.

• Nomenclatural history of Pennsylvanian strata in Kansas (KGS Open-file Report 2022-5 or NGMDB page)
• Lithostratigraphic Correlations of the Upper Desmoinesian and Missourian Stages (Pennsylvanian) in Eastern Kansas (KGS Open-file Report 2022-3)
• Oborny, S., Layzell, A., Ludvigson, G., and Hasiuk, F., 2022, Revision to Nomenclature of the Zarah Subgroup of the Kansas City Group (Pennsylvanian) in Kansas: Midcontinent Geoscience, 3, p. 27-34, https://doi.org/10.17161/mg.v3i.18249.
• Oborny, S., Hasiuk, F., Layzell, A.L., Smith, J.J., in review, Outcrop-to-subsurface stratigraphic correlations of the Upper Desmoinesian and Lower Missourian stages (Pennsylvanian) in eastern Kansas: regional assessment of group boundaries from type, principal, and neostratotype sections: Kansas Geological Survey Bulletin.

• Lead agency -- Kentucky Geological Survey
• Status -- Completed (2022)
• Please address inquiries to Doug Curl (Kentucky Geological Survey) or NGMDB staff.

The Kentucky Geological Survey identified and categorized stratigraphic discontinuities across map boundaries, and developed a set of recommendations for if, and how, these discontinuities should be dealt with. A documentation protocol for geologic map discontinuities in digital geologic map compilations was developed, using Kentucky's statewide 1:24,000 digital geologic map as the foundation of the effort.

• Final report (2023)

• Lead agency -- Maine Geological Survey
• Cooperating State agencies -- Connecticut Geological Survey, Massachusetts Geological Survey, New Hampshire Geological Survey, Vermont Geological Survey
• Status -- Completed. Proposal approved 2021, work began 2023, final products posted December 2023.
• Please address inquiries to Maine Geological Survey or NGMDB staff.

While the basic concept of New England as a Paleozoic plate tectonic collision zone was established in the 1970’s, recent advances in high-precision geochronology have allowed workers to recognize an increasingly complex array of continental fragments, microcontinents, island arcs, sedimentary basins, and other stratigraphic elements that are incorporated in an intricately deformed, repeatedly metamorphosed, and highly intruded orogenic system.

The existing bedrock maps for the six New England states were compiled at different scales at different times ranging from 1983 to 2011. Each map not only represents the state of knowledge at the time it was made, but also is a reflection of the tectonic model and stratigraphic perspective selected by its compilers. For these reasons there are inconsistencies of many types across state boundaries. In addition, more recent mapping has shown places in every state where the state maps need to be updated.

In this initial collaborative project of the New England States Geologic Mapping Coalition (NESGMC) we reviewed the existing state of knowledge, identified areas where we could see that regional and local stratigraphic problems exist, especially ones that affect cross-border areas, and offered recommendations for addressing them. The goal was not to solve stratigraphic problems, but to guide next steps such as designing research proposals, directing state or federally-funded mapping programs, or initiating academic research projects on stratigraphy-related topics, big and small. The resulting report and accompanying robust citations file in csv format are freely available at the Digital Maine Repository at https://digitalmaine.com/geo_docs/194/. Other project documents, including the proposal and workplan, are posted on the NESGMC website.

• See final report and preliminary documents at the NESGMC website

• Lead agency -- Pennsylvania Geological Survey
• Status -- Completed March, 2023
• Please address inquiries to Gale Blackmer (Pennsylvania Geological Survey) or NGMDB staff.

The Pennsylvania Geological Survey has completed the initial compilation of the Pennsylvania Universal Bedrock Geologic Units Table through an in-depth literature review of current formal and informal bedrock geologic units that appear on agency maps and reports. The review revealed previous inconsistencies that had yet to be resolved and new inconsistencies that had not yet been discovered. Following an internal review of these discrepancies, feedback from the geologic community was sought. Through this continuous open discussion with professionals throughout the community, fostered by the survey’s stratigraphic forum series, the inconsistencies in nomenclature and correlation across Pennsylvania were addressed. This project provided the opportunity to identify areas, both geographically and stratigraphically, in which knowledge is generally lacking. While quick resolutions were sometimes possible, many questions were more complex and will ultimately require additional research or field work. The ability to pinpoint the areas in which understanding is lacking will help to guide future research at the survey. The continuation of the modernization of Pennsylvania’s stratigraphic framework include pinpointing the area of the State, or the general location, in which each unit can be found (geographic extent) and continuing to work through the stratigraphic column into younger units, including unconsolidated deposits.

The results of this project will provide the foundation on which to build a series of updated stratigraphic columns for regions of the state. The results also provide a framework for the Pennsylvania Geological Survey plans to build an inventory of outcrop and subsurface core sections that will allow geologists to examine representative examples of the formations in different regions. The nomenclature changes recommended as a result of this investigation will be formalized through publication of geological reports or documentation through USGS's Professional Paper series "Stratigraphic Notes". All nomenclature updates will be delivered to NGMDB for inclusion in Geolex. The information that comprises the new stratigraphic framework will be released to the public through Pennsylvania Geologic Data Exploration (PaGEODE) website.

• Final report (2022)
• Spreadsheets for all formal units

• Lead agency -- Geological Survey of Alabama
• Cooperating State agencies -- Arkansas Geological Survey, Louisiana Geological Survey, Mississippi Office of Geology, Tennessee Geological Survey, Texas Bureau of Economic Geology
• Status -- In Progress; begun in 2022
• Please address inquiries to Greg Guthrie (Geological Survey of Alabama) or NGMDB staff.

The Geological Survey of Alabama is leading an extension of its East Gulf Coastal Plain initiative, to focus on stratigraphic units in the West Gulf Coastal Plain, including deposits in the Mississippi Embayment. Significant outcrop and subcrop differences in Mesozoic and Cenozoic strata are present throughout the stratigraphic section in these regions that comprise the northeastern, central, and western part of the northern Gulf of Mexico basin and these are reflected in the different nomenclature used by each state.

An initial working group meeting was held in Baton Rouge, Louisiana on July 26, 2023. Representatives from each of the participating states were in attendance either in person or virtually. The meeting had several objectives: (a) to introduce members of the working group, (b) to provide an overview of the project, (c) to outline the investigative model utilized by the East Gulf Coast Strategic Reconciliation Working Group to accomplish similar goals, (d) to discuss individual concerns and needs of each of the working group participants, (e) to develop an action plan for work to be accomplished, and (f) to establish a timeline for project implementation.

Several objectives have been accomplished or begun following the initial meeting, including:
- Researching historic and current Mesozoic and Cenozoic stratigraphic nomenclature used in Texas, Louisiana, Arkansas, Mississippi, and Tennessee.
- Descriptions of all of the stratigraphic units in each of the participating states that will be provided to update Geolex have been prepared.
- A working draft of a regional stratigraphic correlation chart incorporating current stratigraphic nomenclature was produced. An item to note from the chart is that some states are "lumpers" and some states are "splitters" in terms of how detailed individual stratigraphic units are defined. This is primarily a reflection of the research focus in individual areas.
- Work has begun on the production of regional cross sections, using primarily oil and gas wells, to display along and across strike stratigraphic variations. The cross sections incorporate data from geophysical logs to identify formation tops and structural features and will be used to assess the presence or absence of stratigraphic units across state boundaries and to assist with nomenclature reconciliation.
- Field mapping at 1:100,000 scale was begun in Arkansas to delineate individual formations in the Tertiary Claiborne Group.

A project extension was requested and granted extending the project deadline from October 1, 2023, to April 30, 2025, as a result of time required to finalize each of the subawards to the working group states.

A second in-person meeting was held in El Dorado, Arkansas March 6-7, 2024. Project updates were provided by each of the working group members and discussions were held on topics ranging from specific nomenclature issues to future projects. A field trip to selected sites in the Claiborne and Wilcox groups was led by members of the Arkansas Geological Survey.

An abstract documenting the progress to date was prepared and presented during a symposia entitled "Interstate Collaboration in the Southeast US -- State Geological Surveys Working Towards Stratigraphic and Lithologic Equivalencies to Address Mapping Discrepancies More Effectively" at the 2024 Southeastern Section meeting of the Geological Society of America meeting in Asheville, North Carolina, April 14-17, 2024. A copy of the abstract and presentation are available below.

• Progress report (Oct., 2023)
• Presentation, April, 2024 (Geological Society of America, Southeastern Section meeting)

• Lead agency -- South Carolina Geological Survey
• Cooperating State agencies -- Florida Geological Survey, North Carolina Geological Survey, Virginia Division of Geology and Mineral Resources
• Status -- In Progress; begun in late 2023
• Please address inquiries to Will Doar and Katie Luciano (South Carolina Geological Survey) or NGMDB staff.

The South Carolina Geological Survey is leading a Southeastern Atlantic Coastal Plain working group, to include the geological surveys of Virginia, North Carolina, South Carolina, and Florida. Representation from Georgia will come from interested universities. The purpose is to address stratigraphic issues, in part to facilitate the orderly development of interstate stratigraphic correlations.

• Lead agency -- Illinois State Geological Survey
• Cooperating State agencies -- Kentucky Geological Survey, Missouri Geological Survey
• Status -- In Progress; begun in late 2023
• Please address inquiries to Joe Devera and Scott Elrick (Illinois State Geological Survey) or NGMDB staff.

The Illinois State Geological Survey will develop a unified geological nomenclature of the Midcontinent stratigraphy of the Coastal Plains province of Illinois, Kentucky and Missouri. Outcrop and subcrop differences in nomenclature from Mesozoic and Cenozoic strata are present throughout the stratigraphic sections of the upper Mississippi Embayment region of southern Illinois, southeastern Missouri, and western Kentucky. The project will convene a Midcontinent Coastal Plains Province working group, managed by the Illinois State Geological Survey and comprised of stratigraphic experts from the three states, to address interstate stratigraphic frameworks, terminology discrepancies, and resolve 'state-line faults'.

• Lead agency -- Delaware Geological Survey
• Cooperating State agencies -- Maryland Geological Survey, New Jersey Geological and Water Survey, Virginia Division of Geology and Mineral Resources
• Status -- In Progress; begun in late 2023
• Please address inquiries to Peter McLaughlin (Delaware Geological Survey) or NGMDB staff.

The Delaware Geological Survey will be documenting and sharing the data framework used for the two previous MAtStrat Cooperative Agreements. The project has two goals: 1) to document how MAtStrat data and information types were collected, organized, and stored, and 2) to transform the project data framework into a collaborative data-sharing hub for Middle Atlantic Coastal Plain stratigraphic equivalency researchers that provides access to data assembled during the MAtStrat project and standards for addition of future data.

• Lead agency -- Iowa Geological Survey
• Cooperating State agencies -- Kansas Geological Survey, Missouri Geological Survey, Nebraska Geological Survey
• Status -- In Progress; begun in late 2024
• Please address inquiries to Stephanie Tassier-Surine (Iowa Geological Survey) or NGMDB staff.

Pre-Illinois Episode glacial deposits blanket the midcontinent and date between 0.5-2.6 Ma. Early researchers used the terms "Kansan" and "Nebraskan" to delineate these tills as no more than two had been identified at the same locality. Later work in the 1970's and 1980's revealed the complexity of the sequence, including the presence of multiple tills and paleosols beneath the so-called "Nebraskan" till and the recognition that the Pearlette ash bed, which was used to mark the end of Kansan time, actually consisted of multiple distinct ash beds with significantly different ages. Hence, the two-part stratigraphy was abandoned in favor of labelling these glacial deposits as "Pre-Illinoian"".

Despite the fact that at least seven pre-Illinoian tills have been identified, dating these deposits and correlating them remains problematic. This problem stems in part because several reliable dating methods (e.g. radiocarbon and optically stimulated luminescence) cannot be applied to deposits that are this old, limiting chronostratigraphic approaches to dating volcanic ash deposits when present, paleomagnetism of tills, and cosmogenic nuclide exposure dating of paleosols, each of which has limitations. In addition, few sites contain multiple till bodies, and studies conducted by geologic surveys and other researchers used varied methodologies and terminology, further limiting the ability for regional correlation. Inconsistent stratigraphic nomenclature and boundary delineation have historically hindered research and stratigraphic correlations on a regional, national, and even global scale. These inconsistencies have created confusion in the academic and research communities, as well as for those working in the working group states.

Therefore, the geological surveys from Iowa, Kansas, Nebraska, and Missouri propose to create a working group to address lithostratigraphic and chronostratigraphic discrepancies within and across state boundaries. Great importance lies in creating a unified regional assessment of pre-Illinoian nomenclature. This study will significantly benefit the individual states and the USGS, as they conduct new geologic mapping studies and work together to refine the Nation's stratigraphic framework, which is applied to purposes ranging from local land-use and groundwater planning to compilation of regional and national-scale geoscience assessments.

• Lead agency -- Illinois State Geological Survey
• Cooperating State agencies -- Indiana Geological and Water Survey, Michigan Geological Survey, Ohio Division of Geological Survey,
• Status -- Will begin in late 2024
• Please address inquiries to David Grimley (Illinois State Geological Survey) or NGMDB staff.

The purpose of this cooperative project will be to help resolve Quaternary (glacial and interglacial) stratigraphic nomenclature and stratigraphic correlations within and among the states of Illinois, Indiana, Michigan, and Ohio. These four states are currently involved in detailed local, regional, and/or statewide Quaternary mapping projects where material- and age-based lithostratigraphic units are used as the primary geologic map units. In addition to reexamining and documenting each state’s stratigraphic column, a primary aim of this project will be to update and refine regional nomenclature and geologic correlations across the Lake Michigan, Huron-Erie, and Saginaw glacial lobes of the Midwest East region. New analytical data (compositional, grain size, geochronological), to be collected as part of this project, will contribute to the characterization and correlation of near-surface geological units.

As stratigraphic names used in State and USGS geologic mapping programs have continually evolved over many decades, updates to the stratigraphic columns are needed periodically to facilitate communication within and among our organizations, to other scientific and statewide agencies, to private industry, to local governments, to the general public, and to scientific collaborators in adjacent states. Better understanding and better documentation of Quaternary stratigraphic units will help the general public find stratigraphic information relevant to the societal issues of material resources, environmental problems, and geologic hazards. Future publication of stratigraphic correlations charts within and among the four states will aid public understanding and use of this information for decision making. Additionally, the updated stratigraphic charts will provide clarity in use across state boundaries and support refinement and accuracy of regional and national-scale geological mapping.

• Lead agency -- Geological Survey of Alabama
• Status -- Will begin in early 2025
• Please address inquiries to Sandy Ebersole (Geological Survey of Alabama) or NGMDB staff.

Consistent and updated stratigraphic nomenclature is important for not only USGS goals, but also for many other geologic, hydrologic, critical mineral, fossil fuel energy, and other projects in this region. An understanding of Gulf Coastal Plain and South Atlantic Coastal Plain aquifers, hydrocarbon reservoirs, critical mineral sources, their stratigraphic occurrence, and correlations are of critical importance, as these are integral to groundwater resource management and critical mineral and oil and natural gas exploration and production. These aquifers and reservoirs are of continual research and mapping focus at the GSA and the many other state geological surveys in the south and southeastern region.

The USGS National Geologic Map Database (NGMDB) project provides an opportunity to contribute to the realization of an integrated geologic map of the nation by addressing stratigraphic correlation and nomenclature issues across state geologic map boundaries. The U.S. Geologic Names Lexicon (Geolex) database is an important part of the NGMDB, as it is the national compilation of geologic names and descriptions of geologic units. The NGMDB and Geolex have been collaborating with state geological surveys to address regional stratigraphic nomenclature issues within and across multiple states, with one goal being to support long-term management of stratigraphic information that supports research and other applications. These Cooperative Agreements (described elsewhere on this Web page) have included a number of multi-state projects across the U.S., and include, for example, those of the southern Coastal Plain: the East Gulf Coastal Plain, the West Gulf Coastal Plain, and the South Atlantic Coastal Plain.

The main goal of this proposed Cooperative Agreement is to produce an organized, formatted compilation of stratigraphic information that can be readily reviewed for consideration of, and ingestion into, Geolex. Stratigraphic information for this compilation will be obtained from the three above-named Cooperative Agreements that address stratigraphy of the southern Coastal Plain.