Dujiali Boron Deposit in Xainza County（6）

Dujiali Boron Deposit is located in the Xainza County，only 8 km to Siling Cuo，the second large lake in northern Tibet，being a lagoon lying northwest of Siling Cuo.The Nagqu-Ali highway runs across the south side of the lake and connects with the Qinghai-Tibet highway in the Amdo County 340 km east of the lake.Transportation is convenient.The deposit ranges 4600-4400 m in elevation with harsh climate and poor ecological conditions.

The deposit occurs in the Quaternary lacustrine chemical sediments and the modern lacustrine brine of the Dujiali lake basin.Besides boron there are mirabilite，idromagnesite，liquid lithium ores，etc.

Solid boron ores are characterized by crystals and clay，chiefly by clay.They are nearly bedded，intercalated by lenses and banded rich boron crystals.The rich borax ores can be classified into three types：powdered，sugary grained and tabular.The ore bodies are bed-like，lenticular or chambered，with B2O3 ranging 17%-35%，being 3-15 cm thick.The boron clay consists of black silt.The gray white carbonaceous clay absorbed free boron and formed the silty boron ores distributed in lenticular form in the upper-middle part of the mirabilite layer，200-2000 m long，200-800 m wide，0.3-0.5 m thick and 3-4.5 m deep.The content of B2O3 averages 3.24%-8.38%，the maximum reaching 13.94%.

Liquid boron ores have two types：lake-water and intercrystalline brine.The lake-water type changes with season.From January to May the lake wa-ter is about 1.5 square kilometers in area，while in rainy season it increases.According to statistics of October 1 9 60 the lake water was 2 8 square kilome-ters in area and 0.1-0.5 m in depth.The content of B2O3 in lake water is aver-agingly 1 344.27 mg/L，that of the intercrystalline brine is 3210 mg/L.

Investigations show that the reserves of B2O3 were 1l 1 200 tons，those temporally unusable amounted to 1.177 million tons（the average content of B2O3 being 0.45%），of which 191000 tons at B2O3≥1.5%.The B2O3 reserves of lake-water boron were 11200 tons and that of the intercrystalline brine were 122100 tons.Besides，reserves of mirabilite were estimated at 178 million tons.

In 1955 the Heihe Team（with Liu Kejun as the director and Wang Wen-bin as the chief geologist）under the Qinghai Petroleum Prospecting Party（No.632 Party）of the Northwest Bureau of Geology under the MGMR carried out petroleum prospecting on the scale 1∶1000000 in the area.When making a reconnaissance according to the report of local people，Zhang Baosheng and Feng Zhiqiang and others of the team found the borax deposit.The Tibet Bu-reau of Geology founded in March 1956 set up the No.821 Party consisting of Fan Minzhong，Wu Guanhua，Zhuang Hejin and others to make a survey on the boron deposit of the Baingoin lake.The party compiled the 1∶5000 topo-graphic-geological sketch map，operated 12 shallow pits，and collected samples from the clay layer.Analyses showed that the maximum B2O3 reached 0.54%，the minimum 0.07%.Boron crystals were found merely from one pit.In 1957 with the removal of the Tibet Bureau of Geology the survey was terminated.However，the urgent demands for boron resources stimulated the geological work.In September 1958 the Qinghai Bureau of Geology formed the Baingoin Lake Geological Party which placed immediately in the agenda the shallow，easily exploitable and processible boron ores of Dujiali.

In 1959 the Baingoin Lake Geological Party formed a 2 5-person salt lake reconnaissance team led by Mao Zhengheng，the director，and Liu Tingrong，the chief geologist，to take over the job of boron prospecting.While drafting the Quaternary geological sketch map Zeng Rong and others found in the first salt terrace a crystal sugar-like“salt”layer.The layer was later confirmed as of borax through sampling and ****ysis and was areally controlled by shallow drills and wells.After a month＇s work the Dujiali Lake boron deposit was as-certained as a promising prospect and was reported to the party.By adjust-ment of technical forces the party formed the Dujiali boron deposit prospecting subparty with Liang Chengbin as the chief and Li Conghui as the chief geolo-gist.The subparty targeted the boron-bearing silt as the main objective.By driving shallow boreholes associated with shallow wells and 1∶25000 geologi-cal mapping，the boron-bearing horizons less than 1 0 m in depth were con-trolled.Altogether 1358 m of shallow wells were driven and 5549 samples were ****yzed，thus the perspective of the deposit was further confirmed.Lat-er the 1∶25000 scale mapping area of Quaternary was expanded and the hy-drogeological sketch survey and the long-term hydrological observations start-ed.The 1∶5000 geological map of the deposit was completed and the orebody was further controlled and outlined.The detailed prospecting work on the rich boron deposit helped satisfy the demands of the 4000-person No.1 Chemical Plant.

In May 1 960 the Tibet Bureau of Geology was re-established and the Bain-goin Lake Geological Party was renamed the Zangbei（northern Tibet）Geolog-ical Party.According to the ore-dressing technology of the No.1 Chemical Plant，the party took the rich ores with cutoff grade of 8%and minimum com-mercial grade over 10%as the main target of prospecting.By the end of 1960 the“Interim report on the development prospecting of the rich ores of the Du-jiali Lake”was submitted.In 1961 the prospecting of the Dujiali deposit was concentrated on the commercial ores at a grade of over 10%in order to meet the demands of the plant.In July 1 961 the Tibet Bureau of Geology，the Zang-bei Geological Party，the working group with the Ministry of Chemical Indus-try and the No.1 Chemical Plant of Tibet decided through consultation thatsince the usable rich ores had already been basically delineated，no more engi-neering would be necessary before the mining specifications were officially de-termined，the geological exploration of the deposit might be brought to a close，and the development exploration could be shifted upon the No.1 Chemi-cal Plant.Thus the prospecting of the Dujiali deposit was ended.In the two-years＇prospecting a total of 948 shallow drillholes covering 33648 m and 752 m of shallow wells were operated.The reserves of economically rich B2O3 ores were verified as of 122000 tons，and the subeconomic ones were 1.232 million tons，which satisfied the requirements of the No.1 Chemical Plant and of the eight foreign countries who requested China earnestly for supplies of borate mineral materials at the Economic Cooperation Conference held in Berlin in 1958.

The prospecting of the Dujiali boron deposit was China＇s first attempt at large-scale prospecting of modern salt lake.Due to the protracted delay of the promulgation of industrial index and of the reserves estimation guidelines the“Report of preliminary exploration of the boron deposits in Dujiali and Bain-goin Lakes of Tibet”was not submitted and approved by the MGMR until Oc-tober 1964.

2010年英语 四级单词表 急急！！

四级核心词汇

系列一

Abandon, aboard, absence, absent, absolute, absorb, abstract, abundant, abuse, academic, accelerate, access, accommodation, accompany, accomplish, accord, accordance, account, accumulate, accurate, accuse, accustomed, achievement, acknowledge, acquaintance, acquire, acquisition, acute, adapt, additional, adequate, adjust, administration, admission, adopt, advanced, advantage, advertise, advisable, advocate, affect, affection, agenda, aggressive, aid, alcohol, alert, alliance, allowance, alter, alternative, aluminum, *******, amaze, ambition, ambitious, ambulance, amuse, ancestor, ancient, anniversary, annoy, annual, anticipate, antique, anxiety, apartment, apparent, appeal, appliance, applicable, applicant, application, apply, appointment, appoint, appreciate, approach, appropriate, approve, approximate, arbitrary, arise, arouse, arrange, arrest, artificial, assemble, assembly, assess, asset, assign, assist, assistance, associate, association, assume, assumption, assure, astonish, athlete, atmosphere, attach, attain, attitude, attraction, attractive, attribute, audience, authority, authorize, auto, automatic, automobile, auxiliary, available, avenue, avoid, award, awful, awkward 121 words

background, bacteria, baggage, balance, bankrupt, banner, bar, barely, barrel, barrier, basically, basis, battery, beam, behalf, behave, behavior, belief, beneath, beneficial, benefit, besides, bid, billion, bind, biology, blank, blast, blend, bloom, boast, bold, bolt, bomb, bond, boom, boost, border, bore, boring, bounce, bound, boundary, bow, brand, breadth, breast, breed, brief, brilliant, budget, bulk, bump, bunch, burden, bureau 56 words

系列二

fabric, facility, factor, faculty, fade, failure, faithful, fame, famine, fancy, fantastic, fantasy, fare, fascinating, fashion, fashionable, fatal, fate, fatigue, faulty, favorable, favorite, fearful, feasible, feature, federal, fee, feedback, fertile, festival, fiber, fierce, finance, financial, fireman, flame, flash, flee, fleet, flexible, flock, flourish, fluent, fluid, focus, folk, forbid, forecast, foreigner, forge, formal, format, formation, former, fortnight, fortunately, foundation, fraction, fragment, frame, framework, frank, freight, frequency, frontier, fruitful, frustrate, fry, fulfill, function, fund, fundamental, funeral, fur, furnish, furthermore, fuss

77 words

gap, garbage, gardener, gasoline, gaze, generally, generate, generous, genius, genuine, germ, gesture, giant, glimpse, global, glorious, glory, glow, glue, goodness, govern, governor, grab, graceful, gradual, graduate, grand, grant, graph, grasp, grateful, gratitude, greedy, greenhouse, grind, grip, grocer, gross, guarantee, guidance, guideline, guilty, gulf, gymnasium

44 words

halt, handful, handle, handy, harbor, harden, hardship, harm, harmony, harsh, haste, hatred, hazard, headquarters, heal, heap, heave, hence, herd, heroic, hesitate, highlight, highway, hint, historic, historical, hollow, holy, honorable, hook, horizon, horizontal, horrible, horror, host, hostile, household, humble, hunt 39 words

ideal, identical, identify, identity, idle, ignorance, ignorant, illegal, illustrate, imitate, immense, impact, impatient, implement, implication, impose, impress, impression, impressive, improvement, incident, incline, increasingly, incredible, independence, independent, indicate, indifferent, indispensable, individual, industrial, inevitable, infect, inferior, infinite, inflation, influence, influential, inform, ingredient, inhabitant, inherit, initial, injection, injure, injury, innocent, input, inquire, insect, insert, insight, inspect, inspire, install, instinct, institution, instruct, instrument, insult, insurance, insure, integrate, intellectual, intelligence, intelligent, intend, intense, intensity, intensive, intention, interaction, interfere, interior, intermediate, internal, interpretation, interrupt, interval, interview, intimate, introduction, invade, invasion, invest, investigate, involve, isolate, issue, item

90 words

am, jealous, joint, journal, journalist, judgment, junior, justice, justify

9 words

Keen, kid, kindness, kingdom, kneel, knot

6 words

Label, lag, landscape, lane, largely, latter, launch, layer, layout, leadership, leak, lean, leap, lease, legal, legislation, leisure, lest, liable, liberal, liberate, liberty, license, lick, lid, lightning, limitation, link, liquid, liquor, liter, literary, literature, liver, loaf, loan, lobby, local, locate, location, lodge, log, loop, loose, loosen, lord, lower, loyal, loyalty, luggage, lump, lung, luxury

53 words

machinery, magic, magnet, magnetic, magnificent, maintain, maintenance, manner, manual, manufacture, margin, marine, marvelous, mask, massive, mature, maximum, medal, media, medium, melt, memorial, merchant, mercy, mere, mild, military, minimum, minor, minority, miracle, miserable, mislead, missing, mission, misunderstand, mixture, mode, moderate, modest, modify, moist, mold, molecule, monument, mood, moral, moreover, motion, motivate, motive, multiple, multiply, mutual, mysterious, mystery, myth

57 words

namely, nationality, navigation, necessarily, necessity, negative, neglect, negotiate, neighborhood, nerve, neutral, nevertheless, nightmare, normally, noticeable, notify, notion, nuclear, nucleus, nuisance, numerous, nursery

22 words

objection, objective, obligation, oblige, observe, obstacle, obtain, obvious, occasion, occasional, occupation, occupy, occurrence, odd, offend, offense, offensive, omit, operational, opponent, opportunity, oppose, optical, optimistic, option, orbit, orderly, organic, organization, origin, outcome, outlet, outline, outset, outstanding, overall, overcome, overlook, overseas, overtake, owing

41 words

系列三

pace, package, painful, panic, parcel, parliament, partial, participate, particle, particularly, partner, passion, peak, peculiar, peer, penalty, penetrate, perceive, perception, performance, permanent, permission, persist, personality, personnel, perspective, pessimistic, phenomenon, physical, pierce, plastic, pledge, plentiful, poison, poisonous, policy, polish, poll, pollute, pollution, portable, portion, pose, positive, possess, postpone, potential, poverty, powerful, practically, precaution, preceding, precise, precision, predict, preferable, preference, prejudice, preliminary, preparation, presence, presentation, preserve, pressure, presumably, prevail, previous, primary, prime, primitive, principal, principle, prior, priority, private, privilege, procedure, proceed, process, procession, product, profession, professional, profit, progressive, prohibit, project, prominent, promote, prompt, proof, property, proportion, proposal, propose, prospect, prosperity, prosperous, protection, protein, protest, provided, provision, provoke, psychological, publish, punctual, purchase, pursue, puzzle

已经从195个减到 110 words

qualification, qualify, quit, quote

4 words

radiation, range, rank, rare, rarely, rate, rational, raw, react, realistic, reality, realm, rear, reasonable, recall, reception, recession, recognize, recommend, recovery, recreation, recruit, reduction, reference, refine, reflect, reflection, reform, refresh, regarding, regardless, region, register, regulate, regulation, reinforce, reject, relax, release, relevant, reliable, relief, relieve, religion, religious, reluctant, rely, remarkable, remedy, remote, removal, render, repetition, replace, represent, representative, reproduce, reputation, requirement, rescue, resemble, reservation, reserve, resident, resign, resist, resistance, resistant, resolution, resolve, resort, resource, respectively, respond, response, responsibility, responsible, restless, restore, restrain, restraint, restrict, resume, retail, retain, retire, reveal, reverse, revolutionary, reward, rid, ridiculous, rigid, rival, roar, rob, robot, rocket, rotate, rouse, routine, royal, rub, rude, rumor, rural

106 words

sacrifice, sake, sale**an, sample, sanction, satisfactory, saving, scale, scan, scandal, scarce, scare, scatter, scenery, schedule, scheme, scholarship, scope, scrape, scratch, screen, section, sector, secure, security, select, selection, selfish, senior, sensible, sensitive, sequence, series, settlement, severe, shallow, shed, sheer, shelter, shield, shift, shiver, shortage, shrink, sightseeing, signal, significance, significant, similarly, simplicity, sincere, sketch, skilful, slender, slight, **ash, snap, soak, soar, social, solar, sole, solemn, solution, solve, sophisticated, sore, sorrow, source, span, spark, species, specific, specify, spectacular, speculate, sphere, spill, spiritual, spit, spite, split, spoil, sponsor, spot, spur, squeeze, stable, stack, staff, stain, stale, starve, statement, static, statistic, statue, status, steady, steep, sticky, stiff, stimulate, stir, stock, stoop, storage, strain, strategic, strategy, strengthen, stress, stretch, striking, string, strip, stroke, structure, stuff, submerge, submit, subsequent, substance, substantial, substitute, subtract, suburb, succession, successive, suck, sufficient, suggestion, summit, superb, superficial, superior, supplement, supreme, surgery, surplus, surrender, surround, survey, survival, survive, suspect, suspend, suspicion, sustain, swallow, sway, swear, swell, swift, swing, switch, symbol, sympathetic, sympathy, symptom, synthetic, systematic

162 words

tackle, talent, tame, tank, target, technician, technology, tedious, teenager, temper, temporary, temptation, tend, tendency, tender, tense, tension, terminal, territory, terror, textile, theme, theoretical, theory, therapy, thermometer, thirst, thorough, thoughtful, threat, threaten, thrive, thrust, thunder, tide, tidy, timber, tissue, title, toast, tolerance, tolerate, topic, torture, tough, trace, tradition, tragedy, trail, transfer, transform, translation, tran**ission, tran**it, transparent, transport, transportation, trap, trash, treatment, treaty, tremble, tremendous, trend, trial, triangle, trim, triumph, troop, tropical, troublesome, tunnel, tutor, twist, typical

75 words

ultimate, umbrella, uncover, undergo, underground, underline, undertake, undoubtedly, uneasy, unexpected, unfortunately, union, unique, unity, universal, universe, unload, upper, upright, upset, up-to-date, urban, urge, urgent, usage, useless, utility, utilize, utmost, utter

30 words

vacant, vacuum, vague, vain, valid, vanish, vapor, variable, variation, vary, vehicle, venture, verify, version, vertical, vessel, veteran, via, vibrate, vice, victim, video, view, viewpoint, vigorous, violate, violence, violent, virtual, virtually, virtue, virus, visible, vision, visual, vital, vitamin, vivid, vocabulary, volcano, volume, voluntary, volunteer,vote

44 words

Wage, waist, waken, wander, warmth, waterproof, wax, weaken, wealthy, weapon, weave, weekday, weep, welfare, whale, whatsoever, whereas, wicked, widen, widespread, widow, wisdom, wit, withdraw, withstand, witness, wool, workman, workshop, worldwide, worm, worship, worthless, worthwhile, worthy, wrap, wreck, wrist

8 words

X没有核心单词

Yawn, yield, youngster

Zone