S U M M A R YTen tensor magnetotelluric (MT) soundings have been acquired in a 54 km long profile across the South Pole area, East Antarctica. The MT transect was offset from the South Pole station ∼5 km and oriented 210 grid north, approximately normal to the Trans-Antarctic Mountains. Surveying around South Pole station was pursued for four main reasons. First, we sought to illuminate first-order structure and physico-chemical state (temperatures, fluids, melts) of the crust and upper mantle of this part of East Antarctica. Secondly, conditions around the South Pole differ from those of previous MT experience at central West Antarctica, so that the project would help to define MT surveying feasibility over the entire continent. Thirdly, the results would provide a crustal response baseline for possible long-term MT monitoring to deep upper mantle depths at the South Pole. Fourthly, because Antarctic logistics are difficult, support facilities at the South Pole enable relatively efficient survey procedures. In making the MT measurements, the high electrical contact impedance at the electrode-firn interface was overcome using a custom-design electrode pre-amplifier at the electrode with low output impedance to the remainder of the recording electronics. Non-plane-wave effects in the data were suppressed using a robust jackknife procedure that emphasized outlier removal from the vertical magnetic field records. Good quality data were obtained, but the rate of collection was hampered by low geomagnetic activity and wind-generated, electrostatic noise induced in the ice. Profile data were inverted using a 2-D algorithm that damps model departures from an a priori structure, in this case a smooth 1-D profile obtained from inversion of an integral of the TM mode impedance along the profile. Inverse models show clear evidence for a pronounced (∼1 km thickness), conductive section below the ice tentatively correlated with porous sediments of the Beacon Supergroup. Substantial variations in sedimentary conductance are inferred, which may translate into commensurate variations in sediment thickness. Low resistivities below ∼30 km suggest thermal activity in the lower crust and upper mantle, and mantle support for this region of elevated East Antarctica. This contrasts with resistivity structure imaged previously in central West Antarctica, where resistivity remains high into the upper mantle consistent with a fossil state of extensional activity there.

During the 1994–1995 austral summer field season, we collected twelve, high‐quality MT soundings over the Byrd Subglacial Basin of central West Antarctica (82°36′S lat., 118°14′W long, approx.) in the period range 0.01 s to 400 s. Ten equispaced sites in a 54 km profile cross regional aeromagnetic trends and complement seismic reflection and refraction results collected by others. Our purposes were to prove such measurements were feasible over the 2 km thick interior ice sheet, and to show from deep electrical resistivity whether the Byrd Basin comprises an active rift environment. The difficult acquisition of electric field data on ice was overcome using a custom electrometer system, with preamplifiers located at the electrode sites to buffer the high contact impedances of the ice as close to the source as possible. Two‐dimensional modeling of the profile shows that resistivity of the deep crust and upper mantle is about 2000–3000 ohm‐m to 100 km depth or more. This is much higher than observed in active extensional regimes, suggesting that the current state of rifting, at least in this part of central West Antarctica, is dormant.

The implementation of a TH program to improve the consistency of care for patients in NICUs is feasible using standard-quality improvement methodology. The successful introduction of new interventions such as TH to the NICU culture requires a collaborative multidisciplinary team, use of a systematic quality improvement process, and perseverance.

PLCS is associated with severe neonatal pulmonary morbidity, but not with severe ROP. Further investigation is warranted to validate these results.