时间:2019-02-24 作者:英语课 分类:英语听力文摘 English Digest


英语课

  Don: Hey, Yael, Have you heard? We've discovered two new oceans?

Yael: Where?

D: On Mars. Well, they aren't there any longer, but they were there a few billion years ago.

Y: I thought scientists weren't sure if Mars had oceans or not.

D: They weren't. The Mars Opportunity Rover found sulfates and other salts in the soil that were left behind when standing 1 water evaporated. It also discovered cross-bedding in the soil which was created by water ripples 2, and tiny mineral deposits  called blueberries that only appear if water is present. The northern lowlands of Mars looked like there might have been an ocean there, but there wasn't definite proof.

Y: So, what has changed their minds?

D: Gamma Ray evidence.

Y: That sounds exciting.

D: It is. The Mars Odyssey 3 spacecraft had a gamma-ray spectrometer onboard that  could detect elements buried as much as a third of a meter, or thirteen inches, below  the soil. Scientists used the spectrometer to measure the amount of potassium, thorium, and iron above and below what they thought to be the shoreline of ancient   oceans. They expected to see low concentrations above the shoreline and larger concentrations below. That would indicate that the elements had been leached 4 out of the soil by the water.

Y: So, what did they find?

D: They found the shorelines of a younger ocean about ten times the size of the Mediterranean 5 Sea, and an older ocean twice that size.

Y: It's too bad those oceans still aren't there.

D: Yeah. It sure would be a great spot for a cruise.



n.持续,地位;adj.永久的,不动的,直立的,不流动的
  • After the earthquake only a few houses were left standing.地震过后只有几幢房屋还立着。
  • They're standing out against any change in the law.他们坚决反对对法律做任何修改。
逐渐扩散的感觉( ripple的名词复数 )
  • The moon danced on the ripples. 月亮在涟漪上舞动。
  • The sea leaves ripples on the sand. 海水在沙滩上留下了波痕。
n.长途冒险旅行;一连串的冒险
  • The march to Travnik was the final stretch of a 16-hour odyssey.去特拉夫尼克的这段路是长达16小时艰险旅行的最后一程。
  • His odyssey of passion, friendship,love,and revenge was now finished.他的热情、友谊、爱情和复仇的漫长历程,到此结束了。
v.(将化学品、矿物质等)过滤( leach的过去式和过去分词 );(液体)过滤,滤去
  • They believe that the humic materials are leached from decaying plant materials. 他们认为腐植物料是从腐烂的植物体浸沥而来。 来自辞典例句
  • The concept holds that uranium is leached by groundwater from tuffeceous rocks. 该理论认为,来自凝灰岩的地下水淋蚀铀。 来自辞典例句
adj.地中海的;地中海沿岸的
  • The houses are Mediterranean in character.这些房子都属地中海风格。
  • Gibraltar is the key to the Mediterranean.直布罗陀是地中海的要冲。
学英语单词
Aboriginals
accumulated earning tax
amors
anepithymia
antirecipocal circuit
apiose
army list, Army List
Autocompetition
batten ends
Bender Cassim
blows you off
boiling holes
cancerettes
cardiac dwarf
chained connection
chiang kan
choupori
chuuch
cleaning fan
Clinton County
cognitive development theory
conoce
cranlan
devisacope
directorate of standards
dredge
drive key
farmans
fine cargo
fore-lying
frequency primary standard
general nature
give free transportation of
homeyer
horseway
idle labor
in-situ soil test
incalculably
inland distribution depot
instantaneous total closure
intracapsular ligaments
isonomia
jurisprudentially
kordax (greece)
Kornilow's reflex
lacrimatories
lid spring
low voltage commutator
Madarao-yama
ministerial standard
monolithic photodiode
multiple virtual storage
nanopaper
nar nar
non-foaming oil
nonbarotropic
NSHS
on-line refuelling
one-year file
out-Herods
overmodulate
Pandion haliaetus
played with fire
political life
polyaoxylin
Posadasis spheriforme
pot limit
potentises
precast prestressed concrete
prefocation
professional dancer
protactinium(iv) oxide
protoplasma
Qin dynasty
record level
ReLC
resonant wire drawing force meter
Rhodininae
roadway
sequential testing
shahjahan
spheroidal weathering
spline surface
stock adjustment demand function
strut rod
sun-2 workstation
superpetrosal
superselling
telephone dials
tiruchchendur (tiruchendur)
toll line
transfunding
unfutured
unhorsed
uniform circular motion
us wrote
volumetric concentration
well-closed containet
westerfield
wolfram lamp
zotepine
zymogen