About Susquehanna Shale Hills CZO

Our research promotes the understanding of how a forested, first-order catchment of shale bedrock evolves over multiple time scales in a temperate climate.

The Shale Hills catchment is part of the Penn State Experimental Forest Lands and has been undergoing research since the 1970's.

The Shale Hills watershed along with a sister catchment, Leading Ridge watershed, have been the focus of long-term studies since 1958. Originally established to evaluate “best management practices” in forested and managed watersheds, today’s Susquehanna Shale Hills CZO is building upon legacy data such as streamflow, precipitation, climate and water quality.

Susquehanna Shale Hills CZO is located in central Pennsylvania. Its primary partner organizations are NSF and The Pennsylvania State University.

Science Questions:

  • How does water sculpt a landscape on shale bedrock?
  • What controls the hydrologic and elemental budgets of the catchment?
  • What are the rates and mechanisms of important hydrological, ecological, and geochemical processes?

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About Christina River Basin CZO

We integrate knowledge of water, mineral, and carbon cycles to quantify human impact on Critical Zone carbon sequestration — from soils to sea.

Point Lookout

The Christina River Basin and its four sub-basins may be one of the best studied watersheds of its size in the nation. Studies include seminal fluvial geomorphology of the Brandywine Creek by Luna Leopold and extensive long-term monitoring efforts by Stroud Water Research Center, EPA, USGS, and others. Our CZO is located in the Piedmont and Atlantic Coastal Plain which provides drinking water to a million people in Delaware and Pennsylvania.

Christina River Basin CZO is located in southeastern Pennsylvania and northern Delaware. Its primary partner organizations are NSFStroud Water Research Center, and University of Delaware.

Science Questions:

  • Are mineral and carbon mixing processes rate-limiting to watershed-scale carbon sequestration, chemical weathering, and soil production?
  • Do humans accelerate carbon-mineral mixing rates, and is this significant to local, regional, and global budgets?

Learn more at