Ship-to-shore webcast 遠端視訊連線訪問
Guest: Dr. Keir Becker 契爾·貝克教授
Dr. Keir Becker is a professor at the
Rosenstiel School of Marine and Atmospheric Science, University of Miami. His
expertise is in heat flow and hydrothermal
circulation in the oceanic crust; permeability and porosity of oceanic crust;
borehole hydrogeological observatories. He has participated in many drilling
lags of Ocean Drilling Program and Integrated Ocean Drilling Program. He has
also have lots of dive experiences. Dr. Becker participated in the design of
CORK observatory and is a pioneer scientist to use CORK observatory to conduct
in situ experiments obtain data for hydrogeological and seismic studies. To
know more about CORK, please read his paper “A review of CORK designs and
operations during the Ocean Drilling Program” (link provided at the end of the article).
貝克教授任教於邁阿密大學大氣海洋學院，他的專長是測量熱流量與水壓的變化，來了解岩石的總孔隙度與空隙的連通度，並將這些資料運用在海洋岩石中的熱液循環的研究，他參與過許多的海洋鑽探航次，以及有許多的使用研究潛水艇的經驗。他是水下觀測井的設計者之一，也是最早使用水下觀測井來作實驗以了解海洋岩石圈中的水文系統的科學家之一，在一篇他撰寫的文章中，他詳細的介紹了過去三十年來，水下觀測井設計與建造的來龍去脈。
Here is a short excerpt of the historic review
in this article: The origins of the CORK experiment can be traced back to discussions
during a 1987 workshop on wireline reentry of
deep-sea boreholes. By that time, considerable experience had been gained in
interpreting thermal observations* of vertical flow in Deep Sea Drilling
Project (DSDP) and ODP holes left open between permeable formation and ocean
bottom water (e.g., Hyndman et al., 1976; Becker et al., 1983). However, we
recognized that such borehole flow, which seemed to be fairly common in holes
penetrating through sediments into oceanic basement, represented serious perturbations
to the hydrological systems we were attempting to study via scientific
ocean drilling; thus, some sort of sealed-hole experiment was necessary to allow
reestablishment of equilibrium in in situ conditions to understand
hydrogeologic state and processes. ……The first two
installations, …… were successfully completed during Leg 139 in the summer of 1991 (Davis et al.,1992).
* Back in 1960s, scientists have made
calculations based on the cooling of oceanic crust to estimate the temperature
of surface sediments on the seafloor. However, the actual measured surface sediment
temperatures are much cooler than the estimated values. Scientists proposed
that there must be hydrothermal circulation to remove the heat from the oceanic
crust. That leads to the discovery of hydrothermal vents in the late 1970s. The
more rapid and larger volume of hydrothermal circulation, the faster the
cooling.
