Abstract:
The SWAIS2C project is an international partnership of 10 countries and the International Continental Scientific Drilling Program (ICDP) that aims to investigate the stability of the West Antarctic Ice Sheet in a warmer-than-present world from geological archives.
Here we present the initial scientific findings from the SWAIS2C project’s 217 m-long drill core recovered during the 2025/26 field season from beneath Crary Ice Rise (CIR), West Antarctica (83° 1.6002’S, 172° 37.5546’W). Drilling at CIR represented a significant technical challenge, requiring melting a ~523 m deep access hole through the ice and then rock drilling into the frozen bedrock below with the Antarctic Intermediate Depth Drill (AIDD) system. The AIDD system successfully cored to 228.12 m below seafloor (mbsf) with 96% core recovery. We divide the core into five lithostratigraphic units (LSU) based on the abundance of varying amounts of mud, sand, gravel and biogenic content as well as the stacking patterns of lithologies. We interpret the facies succession within our core in terms of advance and retreat of the ice sheet. Natural gamma ray downhole logging data supports the placement of these unit boundaries. Initial biostratigraphic age estimates from the lowermost lithostratigraphic unit suggests a maximum age of middle Mio-cene (~17 Ma). The entire record appears to represent discrete intervals of time separated by unconformities evident in seismic profiles that spans from the middle Miocene to Holocene, although this requires verification. The sedimentary packages provide the first direct evidence, recovered below the modern WAIS, for a dynamic, climate sensitive, WAIS from the mid-Miocene onwards. Successful integration of hot water drilling and the AIDD system provides a basis for future subglacial drilling endeavors in the Antarctic deep field where observations are lacking but are urgently needed to better constrain the likely response of WAIS to future warming.
Meeting Place: Baltimore Woods Nature Center
4007 Bishop Hill Rd, Marcellus, NY 13108
Please bring your own high-visibility vest and closed-top shoes (safety-toed boots are recommended). Please also bring safety glasses if you plan to use a rock hammer at the outcrop stop. It is also recommended that you protect yourself against biting insects. This field trip will proceed rain or shine.
Limit = 14 participants.
Attendees desiring PDH credits must pay for PDH credits at the time of registration (see the check box on your registration invoice).
Course Instructor: Guy Swenson, P.G. (Ramboll)
Arrive at Baltimore Woods Nature Center at 8:00 a.m. We will leave the meeting point at 8:30 a.m. Participants will carpool from the meeting point to all stops.
Field Trip Outline:
Introduction Health & Safety Objectives Bedrock Geology of Area Glacial Geology of Area Overview of Field Trip Stops Stop at Marcellus Shale Outcrop Stop for View of Disappearing Lake Area Landslide Stop Learning Assessment Questions
Introduction
Health & Safety
Objectives
Bedrock Geology of Area
Glacial Geology of Area
Overview of Field Trip Stops
Stop at Marcellus Shale Outcrop
Stop for View of Disappearing Lake Area
Landslide Stop
Learning Assessment Questions
Arrive at Baltimore Woods Nature Center at 1:00 p.m. We will leave the meeting point at 1:30 p.m. Participants will carpool from the meeting point to all stops.