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
acoustic beacon pinger
algotherapist
Antoni
aspro
billy-club
blinkingly
bonnet valve
Britai
bucket ladder dredger
cancelli
car yearly repair
carlzon
caterest
center of normal curvature
chemical laser
chsin reflex
circuiters
ciseaux
Clear Springs
control modules
Cypripedium elegans
deallicate
default handler
dictyostelium clavatum
doseberd
dynamic absorber
dyshypophysia
elfazepam
enhart
exenatide
extramarital love
fierk
fixed routing per call
flight class
fossil trees
fuel control valve assembly
glass silvering
gradient slope
happy places
help desks
herbivorously
independent evidence
inseparable polynomial
interlock machine
isoperimetry
Kiloleli
l-lysine monohydrochloride
law of freezing-point depression
lespedeza cuneatas
like new conditions
LVIM
machine tool structure
manganous glycerinophosphate
maximum rotating speed of rotary
mental experiment
microvascular free skin flap
minimum stress-intensity factor
monetary system
moral density
Motilla del Palancar
mukdens
multichannel priority model
noninstructed
oncogenic adenovirus
overcapacity estimate
parallel-rectangular reticle blade
parasuit
parietal artery
PEFRN
percent of purchase liabilities
percentage of completion
pig fishfish
pressure sensitive adhesive
prt valve
qualificators
quartz horizontal magnetometer
rats-tails
re-energizing
revalorize
RF channel synchronization
rigid axle suspension
rope scouring machine
salting in effect
self-reviews
shellsuited
shepherdias
single needle embroidery frame
slow-wittedly
sportsy
stated
Strandbad
tagetes
telephotal
tenaplate
threshold contraction
tiffany
titterer
trans-shipping
ucb
Verruyes
videomaker
Westminster system