try to join the dots

1. From the 1/4 report:

In early November the Chairman, Executive Director and Company Geologist will be traveling to Peru as part of Range's management committee obligations with regard to developing the project and coordinating drilling programs.

2. This was posted on The Gold Report
http://www.theaureport.com/cs/user/print/c....view&id=100276

Solex is an exploration development stage company engaged in the acquisition and exploration of mineral properties, focusing on southern Peru. Solex has four main properties: Macusani (uranium); Vilcabamba (copper-silver-uranium); Pilunani (lead-zinc-silver); and Princesa (silver). The most advanced property is the high-grade Pilunani zinc-silver-lead project. Pilunani, long recognized for its high-grade zinc anomalies at surface, remains largely unexplored by modern methods and a limited drill programme is being formulated for later this year.

Any one of Solex’s properties has the potential to become a company maker, with the Macusani having many of the signs of one that can generate real interest over the next 18 months as a resource starts to be defined. If and when that happens, I don’t expect the company to be friendless as majors can be anticipated to show serious interest! Speculators seeking an early entry into a budding play are advised to strongly consider SOLEX ASAP.” (October 24, 2005).

3.A couple of exerpts from the recent BRW re-BHP:

Regarding petroleum:

'In the next 5 years or so, the company will have exploited most of the best prospects in the Gulf of Mexico so it will have to find a new area for exploration. That could be South Africa or Brunei'

Furtherdown, and regarding gas exploration :

'Long term, we have very good opportunities to grow the business in the Middle East and North Africa'.

4. http://www.hafza.com/page34.html

HORN OF AFRICA FREE ZONE AUTHORITYThe Puntland State of the Federal Republic of Somalia has commissioned October 2004, HAFZA Ltd. of Alberta, Canada to be the operating body for establishing several free zones throughout Puntland. HAFZA Ltd. trades under the business name of the Horn of Africa Free Zone Authority (HAFZA).The philosophy of HAFZA is that, although it is a private corporation, it is to be considered as one of the government’s tools so as to enhance the region economically. HAFZA proposes to achieve this with the development of new and/or redevelopment of existing sea and airports throughout Puntland.... all operating as Free (tax exempt trade) Zones.Special laws and regulations are applied within the free zones different from those applied in the remaining parts of the State of Puntland and the Republic of Somalia.In addition, the Puntland State has provided the whole of the Hafun Peninsula to be transformed into a major tourist and financial centre for the region.Hafun has a size of approximately 200 square miles and reaching approximately 30 miles into the Indian Ocean.In most cases with Free Zones established in other parts of the world, the majority are established by the ruling governments. Those free zones operate with exemptions and facilities to qualify as an investment attraction area for export industries and international trade exchange and/or transit trade.By appointing HAFZA to operate the Horn of Africa Free Zones (hereinafter referred to as HAFZ) it allows investors, developers and major contractors to participate with HAFZA in growing a whole new frontier and share in the wealth by reaching into the heart of Africa and local regions.

5. Vena Intersects 190 Metres of 0.6% Cu on First Hole at Aurora Project
Thursday October 20, 8:01 am ET

TORONTO, ONTARIO--(CCNMatthews - Oct. 20, 2005) - Vena Resources Inc. (TSX VENTURE:VEM - News; LIMA:VEM - News) announces that it has intersected significant copper and molybdenum mineralization in the vertical diamond drill hole #1 at its 100% controlled Aurora project in southern Peru.

Our target for disseminated copper-molybdenum mineralization is a brecciated and fractured quartz monzonite porphyry. Limits and boundary of the breccia mass are not well defined. Mineralized breccia appears to be enclosed in a northwest trending mass of porphyry at least 1.8 km long and 400 to 800 m wide, open on both ends.

Field work continues in an effort to define limits of mineralized breccia. The initial assay results from one of the three core drilling rigs currently working the project appear to confirm, and locally exceed, the results of the widely spaced drilling previously completed by Bear Creek Mining (BCM) in late 1999. BCM's drilling information was re-assayed earlier this year and was reported by the Company on June 8, 2005.

"The Company is very excited about these positive initial results from drill hole DDA-1 at Aurora" said Juan Vegarra, Chairman and CEO of Vena Resources. "Our current drilling is focused on extending the mineralization in all directions. So far, we have completed 3 holes out of a 7 hole campaign and assays will be released as soon as they are ready. " A summary table of DDA-1 follows. Due to lab backlog some assays are pending and will be announced when received by the Company.

----------------------------------------------------------
----------------------------------------------------------
Aurora Project Vertical Hole DDA-1
----------------------------------------------------------
----------------------------------------------------------
Hole From (mt) To (mt) Int (mt) Cu % Mo%
----------------------------------------------------------
----------------------------------------------------------
DDA-1 - 132 132 Pending
132 216 84 0.2%
216 406 190 0.6%
406 548 142 0.2%
548 604 56 Pending
-
Including 256 290 34 0.8%
266 290 24 1.0%

368 486 118 0.02%
----------------------------------------------------------
----------------------------------------------------------


The drilling program and geological studies at the Aurora project are being supervised by Dr. Richard Nielsen and Murray Lytle, Vena's Qualified Person as defined by NI 43-101. Core samples are cut with a diamond saw, with one-half of the core placed in sealed bags, and shipped to Act-Labs Assay Labs in Lima, Peru. The program includes an extensive quality control program for assaying which includes the systematic use of standards, blanks, and field duplicate samples. Secondary laboratories are also used for check assaying.

The average grade reported for the entire 417 meter segment assayed is 0.34% Cu. The graph below depicts that the "belly" of grade is in the middle of the hole. %Cu by downhole depth (m).

To view the graph, please click on the following link:

http://www.ccnmatthews.com/docs/vem1020.pdf

About Vena Resources Inc.

Vena Resources is dedicated to building capital appreciation and creating long term shareholder value by developing the mineral resources and social welfare of Peru. Vena Resources commitment will be demonstrated by deploying its financial resources to aggressively acquire and advance high quality people and assets throughout the country. We seek Safe Harbor.

Statements in this press release regarding the Company's business which are not historical facts are "forward-looking statements" that involve risks and uncertainties, such as estimates and statements that describe the Company's future plans, objectives or goals, including words to the effect that the Company or management expects a stated condition or result to occur. Since forward-looking statements address future events and conditions, by their very nature, they involve inherent risks and uncertainties. Actual results in each case could differ materially from those currently anticipated in such statements.

6. The Chapi section has a total thickness of 360m and is interrupted in the middle by grass-land which corresponds to the strongly altered LLT levels. The lower and upper parts of this section host respectively the “Chapi Bajo” and the “Chapi Alto-Pampa Suyupia” uranium occurrences, the latter representing the biggest uranium deposit of the Macusani area (proven reserves of 10,000 tonnes U3O8).

Cheilletz et al., 1992

7. Copyright 1993 The Times Mirror Company
Los Angeles Times
January 18, 1993
THE OIL FACTOR IN SOMALIA
FOUR AMERICAN PETROLEUM GIANTS HAD AGREEMENTS
WITH THE AFRICAN NATION BEFORE ITS CIVIL WAR BEGAN.
THEY COULD REAP BIG REWARDS IF PEACE IS RESTORED
.
By MARK FINEMAN
DATELINE: MOGADISHU, Somalia
Far beneath the surface of the tragic drama of Somalia, four major U.S. oil companies
are quietly sitting on a prospective fortune in exclusive concessions to explore and
exploit tens of millions of acres of the Somali countryside.
That land, in the opinion of geologists and industry sources, could yield significant
amounts of oil and natural gas if the U.S.- led military mission can restore peace to the
impoverished East African nation.
According to documents obtained by The Times, nearly two-thirds of Somalia was
allocated to the American oil giants Conoco, Amoco, Chevron and Phillips in the final
years before Somalia's pro-U.S. President Mohamed Siad Barre was overthrown and
the nation plunged into chaos in January, 1991. Industry sources said the companies
holding the rights to the most promising concessions are hoping that the Bush
Administration's decision to send U.S. troops to safeguard aid shipments to Somalia
will also help protect their multimillion-dollar investments there.
Officially, the Administration and the State Department insist that the U.S. military
mission in Somalia is strictly humanitarian. Oil industry spokesmen dismissed as
"absurd" and "nonsense" allegations by aid experts, veteran East Africa analysts and
several prominent Somalis that President Bush, a former Texas oilman, was moved to
act in Somalia, at least in part, by the U.S. corporate oil stake.
But corporate and scientific documents disclosed that the American companies are
well positioned to pursue Somalia's most promising potential oil reserves the moment
the nation is pacified. And the State Department and U.S. military officials
acknowledge that one of those oil companies has done more than simply sit back and
hope for pece.
Conoco Inc., the only major multinational corporation to mantain a functioning office
in Mogadishu throughout the past two years of nationwide anarchy, has been directly
involved in the U.S. government's role in the U.N.-sponsored humanitarian military
effort.
Conoco, whose tireless exploration efforts in north-central Somalia reportedly had
yielded the most encouraging prospects just before Siad Barre's fall, permitted its
Mogadishu corporate compound to be transformed into a de facto American embassy
a few days before the U.S. Marines landed in the capital, with Bush's special envoy
using it as his temporary headquarters. In addition, the president of the company's
subsidiary in Somalia won high official praise for serving as the government's
volunteer "facilitator" during the months before and during the U.S. intervention.
Describing the arrangement as "a business relationship," an official spokesman for the
Houston-based parent corporation of Conoco Somalia Ltd. said the U.S. government
was paying rental for it s use of the compound, and he insisted that Conoco was proud
of resident general manager Raymond Marchand's contribution to the U.S.-led
humanitarian effort.
John Geybauer, spokesman for Conoco Oil in Houston, said the company was acting
as "a good corporate citizen and neighbor" in granting the U.S. government's request
to be allowed to rent the compound. The U.S. Embassy and most other buildings and
residential compounds here in the capital were rendered unusable by vandalism and
fierce artillery duels during the clan wars that have consumed Somalia and starved its
people.
In its in- house magazine last month, Conoco reprinted excerpts from a letter of
commendation for Marchand written by U.S. Marine Brig. Gen. Frank Libutti, who
has been acting as military aide to U.S. envoy Robert B. Oakley. In the letter, Libutti
praised the oil official for his role in the initial operation to land Marines on
Mogadishu's beaches in December, and the general concluded, "Without Raymond's
courageous contributions and selfless service, the operation would have failed."
But the close relationship between Conoco and the U.S. intervention force has left
many Somalis and foreign development experts deeply troubled by the blurry line
between the U.S. government and the large oil company, leading many to liken the
Somalia operation to a miniature version of Operation Desert Storm, the U.S.-led
military effort in January, 1991, to drive Iraq from Kuwait and, more broadly,
safeguard the world's largest oil reserves.
"They sent all the wrong signals when Oakley moved into the Conoco compound,"
said one expert on Somalia who worked with one of the four major companies as they
intensified their exploration efforts in the country in the late 1980s.
"It's left everyone thinking the big question here isn't famine relief but oil -- whether
the oil concessions granted under Siad Barre will be transferred if and when peace is
restored," the expert said. "It's potentially worth billions of dollars, and believe me,
that's what the whole game is starting to look like."
Although most oil experts outside Somalia laugh at the suggestion that the nation ever
could rank among the world's major oil producers -- and most maintain that the
international aid mission is intended simply to feed Somalia's starving masses -- no
one doubts that there is oil in Somalia. The only question: How much?
"It's there. There's no doubt there's oil there," said Thomas E. O'Connor, the principal
petroleum engineer for the World Bank, who headed an in-depth, three-year study of
oil prospects in the Gulf of Aden off Somalia's northern coast.
"You don't know until you study a lot further just how much is there," O'Connor said.
"But it has commercial potential. It's got high potential . . . once the Somalis get their
act together."
O'Connor, a professional geologist, based his conclusion on the findings of some of
the world's top petroleum geologists. In a 1991 World Bank-coordinated study,
intended to encourage private investment in the petroleum potential of eight African
nations, the geologists put Somalia and Sudan at the top of the list of prospective
commercial oil producers.
Presenting their results during a three-day conference in London in September, 1991,
two of those geologists, an American and an Egyptian, reported tha t an analysis of
nine exploratory wells drilled in Somalia indicated that the region is "situated within
the oil window, and thus (is) highly prospective for gas and oil." A report by a third
geologist, Z. R. Beydoun, said offshore sites possess "the geolo gical parameters
conducive to the generation, expulsion and trapping of significant amounts of oil and
gas."
Beydoun, who now works for Marathon Oil in London, cautioned in a recent
interview that on the basis of his findings alone, "you cannot say there definitely is
oil," but he added: "The different ingredients for generation of oil are there. The
question is whether the oil generated there has been trapped or whether it dispersed or
evaporated."
Beginni 1986, Conoco, along with Amoco, Chevron, Phillips and, briefly, Shell all
sought and obtained exploration licenses for northern Somalia from Siad Barre's
government. Somalia was soon carved up into concessional blocs, with Conoco,
Amoco and Chevron winning the right to explore and exploit the most promising
ones.
The companies' interest in Somalia clearly predated the World Bank study. It was
grounded in the findings of another, highly successful exploration effort by the Texasbased
Hunt Oil Corp. across the Gulf of Aden in the Arabian Peninsula nation of
Yemen, where geologists disclosed in the mid-1980s that the estimated 1 billion
barrels of Yemeni oil reserves were part of a great underground rift, or valley, that
arced into and across northern Somalia.
Hunt's Yemeni operation, which is now yielding nearly 200,000 barrels of oil a day,
and its implications for the entire region were not lost on then-Vice President George
Bush.
In fact, Bush witnessed it firsthand in April, 1986, when he officially dedicated Hunt's
new $18-million refinery near the ancient Yemeni town of Marib. In remarks during
the event, Bush emphasized the critical value of supporting U.S. corporate efforts to
develop and safeguard potential oil reserves in the region.
In his speech, Bush stressed "the growing strategic importance to the West of
developing crude oil sources in the region away from the Strait of Hormuz,"
according to a report three weeks later in the authoritative Middle East Economic
Survey.
Bush's reference was to the geographical choke point that controls access to the
Persian Gulf and its vast oil reserves. It came at the end of a 10-day Middle East tour
in which the vice president drew fire for appearing to advocate higher oil and gasoline
prices.
"Throughout the course of his 17,000- mile trip, Bush suggested continued low (oil)
prices would jeopardize a domestic oil industry 'vital to the national security interests
of the United States,' which was interpreted at home and abroad as a sign the onetime
oil driller from Texas was coming to the aid of his former associates," United Press
International reported from Washington the day after Bush dedicated Hunt's Yemen
refinery.
No such criticism accompanied Bush's decision late last year to send more than
20,000 U.S. troops to Somalia, widely applauded as a bold and costly step to save an
estimated 2 million Somalis from starvation by opening up relief supply lines and
pacifying the famine-struck nation.
But since the U.S. intervention began, neither the Bush Administration nor any of the
oil companies that had been active in Somalia up until the civil war broke out in early
1991 have commented publicly on Somalia's potential for oil and natural gas
production. Even in private, veteran oil company exploration experts played down
any possible connection between the Administration's move into Somalia and the
corporate concessions at stake.
"In the oil world, Somalia is a fringe exploration area," said one Conoco executive
who asked not to be named. "They've overexaggerated it," he said of the geologists'
optimism about the prospective oil reserves there. And as for Washington's motives in
Somalia, he brushed aside criticisms that have been voiced quietly in Mogadishu,
saying, "With America, there is a genuine humanitarian streak in us . . . that many
other countries and cultures cannot understand."
But the same source added that Conoco's decision to maintain its headquarters in the
Somali capital even after it pulled out the last of its major equipment in the spring of
1992 was certainly not a humanitarian one. And he confirmed that the company,
which has explored Somalia in three major phases beginning in 1952, had achieved
"very good oil shows" -- industry terminology for an exploration phase that often
precedes a major discovery -- just before the war broke out.
"We had these very good shows," he said. "We were pleased. That's why Conoco
stayed on. . . . The people in Houston are convinced there's oil there."
Indeed, the same Conoco World article that praised Conoco's general manager in
Somalia for his role in the humanitarian effort quoted Marchand as saying, "We
stayed because of Somalia's potential for the company and to protect our assets."
Marchand, a French citizen who came to Somalia from Chad after a civil war forced
Conoco to suspend operations there, explained the role played by his firm in helping
set up the U.S.- led pacification mission in Mogadishu.
"When the State Department asked Conoco management for assistance, I was glad to
use the company's influence in Somalia for the success of this mission," he said in the
magazine article. "I just treated it like a company operation -- like moving a rig. I did
it for this operation because the (U.S.) officials weren't familiar with the
environment."
Marchand and his company were clearly familiar with the anarchy into which Somalia
has descended over the past two years -- a nation with no functioning government, no
utilities and few roads, a place ruled loosely by regional warlords.
Of the four U.S. companies holding the Siad Barre-era oil concessions, Conoco is
believed to be the only one that negotiated what spokesman Geybauer called "a
standstill agreement" with an interim government set up by one of Mogadishu's two
principal warlords, Ali Mahdi Mohamed. Industry sources said the other U.S.
companies with contracts in Somalia cited "force majeure" (superior power), a legal
term asserting that they were forced by the war to abandon their exploration efforts
and would return as soon as peace is restored.
"It's going to be very interesting to see whether these agreements are still good," said
Mohamed Jirdeh, a prominent Somali businessman in Mogadishu who is familiar with
the oil-concession agreements. "Whatever Siad did, all those records and contracts, all
disappeared after he fled. . . . And this period has brought with it a deep change of our
society.
"Our country is now very weak, and, of course, the American oil companies are very
strong. This has to be handled very diplomatically, and I think the American
government must move out of the oil business, or at least make clear that there is a
definite line separating the two, if they want to maintain a long-term relationship
here."
Fineman, Times bureau chief in Nicosia, Cyprus, was recently in Somalia

8. 1) The Peruvian agency in charge is the Peruvian Institute of Nuclear Energy (IPEN). The Peruvian Institute of Nuclear Energy (IPEN) is a public decentralized institution of the Energy and Mines Sector with the fundamental mission of promoting and supervising the national development of nuclear energy.

www.ipen.gob.pe/

2) Peru
http://www.worldenergy.org/wec-geis/public...uranium.asp#top

During the course of exploration carried out up to 1992, the Peruvian Nuclear Energy Institute (IPEN) discovered over 40 occurrences of uranium in the Department of Puno, in the south-east of the republic.

3) Peru has a history of Uranium exploration dating back to 1950s under the
authority and control of IPEN. Exploration efforts were halted due to budget
constraints in the early 90s. During the three decades of exploration efforts,
IPEN identified 78 target areas which were classified as high, medium and low
priority.

4) The Macusani district is the most studied area in southern Peru, IPEN
historical reports from Sept. 1983 refer to the areas of Chapi, Corani,
Tantamaco, Huiquiza, Calvario, Concha Rumio, Huachanne, Chilcuno, Chacaconiza
and the surrounding area to the town of Macusani potentially having in the
order of 200,000 tons of Uranium carrying ore with average grades from 0.2% to
12% of U3O8 (Bulletin 71 - Peruvian Geological Society - Sept 1983).

5) Macusani District

Geology and Metallogeny

The petrographic, mineralogical and tectonic characteristics of the
uranium occurrences of Macusani, 150 km to the NNW of Lake Titicaca in Puno,
are such that these mineralizations are unique among Uranium deposits
associated with pyroclastic rocks although similar to the mineralized systems
in Lakeview (Oregon), McDermitt (Nevada), Marysvale (Utah), Makkovik
(Labrador), Rexpar (BC), Mount Pleasant (New Brunswick) and Maureen
(Quensland) in Australia.

6) The studies performed by IPEN showed that:

1. The Uranium ores are found principally at higher levels of the
volcanic sequence;

2. The enclosing rocks are Plio-Quaternary rhyolitic and rhyodacitic
ignimbrites formed by quartz, sanidine, oligoclase, biotite, and
occasionally muscovite and andalusite, in a particular devitrified
vitreous matrix containing numerous lutite clasts;

3. Biotite, smoky quartz and andalusite are very abundant in the
mineralized levels;

4. The metallic ores consists almost exclusively of massive
pitchblende more or less transformed into gummites, phosphates and
silicates of uranium, and very sparse Fe sulphides;

5. The pitchblende fills fractures between a few centimeters and
several meters long and between 1 and 100 mm wide. Some of these
fractures are sub-vertical and are due to the contraction which
gave rise to the columnar disjunction. Others are subhorizontal and
parallel to a system of conjugate ductile shear formations produced
by compaction and settling of the pyroclastic materials containing
the mineralization.

7) Recent exploration of the Macusani area by third parties have found
significant outcrops of the uranium mineral autunite in small fractures in
many areas. Autunite contains 51% uranium by weight and converts into 60% -
65% U3O8.

8) The board of Range Resources Limited (RRS) this morning announced the entry into a Heads of Agreement to acquire a 50.1% option interest in the Corachapi uranium deposit located in Peru. The company explained that the deposit is located in the district of Corani, province of Carabaya, at the area known as Puno. “There are two zones of mineralisation, one being 1.2 kilometres long and 0.25 kilometres wide, and the other 1.6 kilometres long and 0.2 kilometres wide,” the group said.The Peruvian Institute for Nuclear Energy discovered this prospect within its National Prospecting Plan between 1960 and 1975. Additional exploration was conducted by IPEN and IAEA (United Nations).

http://www.egoli.com.au/egoli/egoliNewsVie...D588F9ED30F7%7D

9) http://files.newswire.ca/357/VenaProgram.doc

10. Macusani Volcanics of the Meseta de Quenamari, northern Puno Department, southeast Peru (Figs. 1 and 2), have received world-wide attention owing to their extreme contents of volatile (B, F, Cl) and lithophile (Li, Sn, W and U) rare elements

metal-enriched

strongly peraluminous magmatism in the form of small granitic stocks (8-27 Ma: Clark et al., 1983a; Kontak et al., 1987) plus felsic volcanism including the “Macusani Volcanics” took place. These ignimbritic pyroclastic flows occupy a set of small intramontane basins (Macusani, Crucero, Picotani and Cojata-Ulla Ulla) located ca. 50 km to the north of Lake Titicaca

the geological sketch presented here (Fig. 2) is based on uranium exploration work by INGEMMET (Flores et al., 1983) and IPEN (Valencia and Arroyo, 1985) and on a winter (1989) field reconnaissance mapping and sampling mission

The Macusani basin (Fig. 2) constitutes a roughly quadrilateral depression with a mean elevation of 4400 m (Meseta de Quenamari)

a conservative estimate for the volume of volcanic rocks preserved of 430 km3, if their maximum thickness is 500 m

The volcanic rocks of the Meseta de Quenamari Field are predominantly composed of unwelded, crystal-rich (around 45 vol.%) rhyolitic ash-flow tuffs containing a mixture of ash- and lapilli-size pyroclastic fragments

A summary of the mineralogy of the Macusani volcanics is presented in Figure 3. The mineralogical composition is uniform throughout the field and unusual for volcanic rocks, with phases such as sillimanite, andalusite, muscovite and tourmaline.

F, Li, B2O3 and P2O5 are elevated in the tuffs and reach even higher levels in the obsidian glasses. However, in the tuffs, volatile components may have been lost during explosive eruption and post-emplacement alteration. The trace-element composition of both ash-flow tuffs and obsidian glasses is unusual (Pichavant et al., 1988b3), being comparable to lithophile-enriched granites and pegmatites

Cross-sections along the several rivers cutting the volcanics show distinct flat-lying composite sheets of variable thickness (from 10 to 100 m)

The Huiquiza cross-section (Fig. 6). This section has a maximum thickness of 340 m but is interrupted at its bottom by recent fluviatile deposits of the Macusani river. The section shows two erosional surfaces, the uppermost marked by the reddening of the underlying LLT and the deposition of epiclastic tuffs. The 4350 m LT layer hosts the “Pinocho” uranium mineralization. The epielastic tuff level (ET) hosts some sporadic and discontinuous uranium mineralizations. The Chilcuno Chico sections (Fig. 6). These sections, separated by the Chilcuno Chico river (Fig. 4), were sampled mainly during the 1985 mission, and have a total thickness of 440 m. The Chilcuno North cross-section starts at the Macusani river and is interrupted in the middle by a debris cone. The uppermost part of this section, containing the “Chilcuno VI” uranium occurrence, has not been sampled. The “K3” uranium occurrence (Fig. 4) has been stratigraphically correlated with Chilcuno VI using area1 photograph interpolation and field reconnaissance. The Quychini and Tuturumani K1 showings correspond to an intermediate tuff level hosting also the Cerro Calvario occurrence (see below). The Chilcuno South section starts in the upper basin of the Chilcuno Chico river (Huacahuata village) and corresponds stratigraphically to the upper part of the Chilcuno North section; however, in that section, the epiclastic tuff level has not been recognised.

The Chapi section has a total thickness of 360 m and is interrupted in the middle by grass-land which corresponds to the strongly altered LLT levels. The lower and upper parts of this section host respectively the “Chapi Bajo” and the “Chapi Alto-Pampa Suyupia” uranium occurrences, the latter representing the biggest uranium deposit of the Macusani area (proven reserves of 10,000 tonnes U3O8). The Cerro Calvario uranium occurrence (not located on Figures 4 and 5 and situated approximatively half-way between the Chilcuno and Chapi cross-sections) is hosted by an intermediate lapilli ash-tuff level, corresponding stratigraphically to the Ma89-10 sample. The Chapi Alto LT level contains obsidian glass clasts as inclusions rimmed by a white crust comprising cryptocrystalline quartz and kaolinite.

These cycles may correspond to simple or compound cooling units comprising either single flows or several flow units indistinguishable by 40Ar/39Ar dating. These six fundamental cooling units are dated at (1) 10.0 ± 0.5, (2) 7.8-8.0 ± 0.1, (3) 7.5 ± 0.1, (4) 7.3 ± 0.1, (5) 6.8-7.0 ± 0.1, (b) 6.7 ± 0.1. Variations in aggregate thickness of the tuffs (Chilcuno, 450 m; Orcoyo, 400 m; Chapi, 360 m; Huiquiza, 280 m) reflect irregular pre-volcanic topography and fault development.

The stratigraphic relationships of the uranium mineralization of the Macusani field are defined for the first time. The stratiform and stratabound concentrations are restricted to three main units dated at 7.8 Ma (Chapi Baja), 7.5 Ma (Cerro Calvario, Quychini and Kl) and 6.9-6.8 Ma (Chilcuno VI, K3, Chapi Alto and Pinocho). A maximum age of 6.8-6.9 Ma may, therefore, be assigned to the most important U deposit (Chapi Alto)